anybody played with necking up 6.5 creedmoor to 7mm yet,if so,good,bad,ugly?
- Thread starter sticshooter
- Start date
Re: 7mm creedmoor
http://www.snipershide.com/forum/ubbthre...465#Post3135465
That was one for sale but the seller should have some data.
http://www.snipershide.com/forum/ubbthre...465#Post3135465
That was one for sale but the seller should have some data.
Re: 7mm creedmoor
We were bantering about it here:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=3388322#Post3388322
We were bantering about it here:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=3388322#Post3388322
Re: 7mm creedmoor
The 7mm Creedmore sounds like a great cartridge, 284 in a small package. Is making the brass as easy as just sticking creedmore brass through the FL sizer and that it? If so, I would love to get a barrel in it to test it out on my savage.
The 7mm Creedmore sounds like a great cartridge, 284 in a small package. Is making the brass as easy as just sticking creedmore brass through the FL sizer and that it? If so, I would love to get a barrel in it to test it out on my savage.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">The 7mm Creedmore sounds like a great cartridge, 284 in a small package. Is making the brass as easy as just sticking creedmore brass through the FL sizer and that it? If so, I would love to get a barrel in it to test it out on my savage. </div></div>yea,i would like to try it myself.trying to find out some more info.sent an email to mark at SAC,have'nt got a response yet.he seems to be the one who's done the most testing.i want to rebarrel my 6.5 creedmoor upper with a 7mmcreedmoor on my ar10.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">The 7mm Creedmore sounds like a great cartridge, 284 in a small package. Is making the brass as easy as just sticking creedmore brass through the FL sizer and that it? If so, I would love to get a barrel in it to test it out on my savage. </div></div>yea,i would like to try it myself.trying to find out some more info.sent an email to mark at SAC,have'nt got a response yet.he seems to be the one who's done the most testing.i want to rebarrel my 6.5 creedmoor upper with a 7mmcreedmoor on my ar10.
Re: 7mm creedmoor
I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines?
I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines?
Re: 7mm creedmoor
Necking up can create a dougnut in the neck/shoulder area. It'll need to be throated properly to account for this but not too long so the rifling's out of reach. There's other ways to deal with it but are a pain in the ass.
Necking up can create a dougnut in the neck/shoulder area. It'll need to be throated properly to account for this but not too long so the rifling's out of reach. There's other ways to deal with it but are a pain in the ass.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">The 7mm Creedmore sounds like a great cartridge, 284 in a small package. Is making the brass as easy as just sticking creedmore brass through the FL sizer and that it? If so, I would love to get a barrel in it to test it out on my savage. </div></div>yea,i would like to try it myself.trying to find out some more info.sent an email to mark at SAC,have'nt got a response yet.he seems to be the one who's done the most testing.i want to rebarrel my 6.5 creedmoor upper with a 7mmcreedmoor on my ar10.
</div></div>
Welcome to the darkside (7mm)!
I understand the 7CM IS Marks cartridge.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">The 7mm Creedmore sounds like a great cartridge, 284 in a small package. Is making the brass as easy as just sticking creedmore brass through the FL sizer and that it? If so, I would love to get a barrel in it to test it out on my savage. </div></div>yea,i would like to try it myself.trying to find out some more info.sent an email to mark at SAC,have'nt got a response yet.he seems to be the one who's done the most testing.i want to rebarrel my 6.5 creedmoor upper with a 7mmcreedmoor on my ar10.
</div></div>
Welcome to the darkside (7mm)!
I understand the 7CM IS Marks cartridge.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines? </div></div>
Alpha mags don't really provide room for 2.985" COAL. Figure on ~2.965ish max.
That said, 7CM will fit standard short actions great.
On brass prep: it seems highly likely donuts will be encountered. Usually is when necking up. Best way I know to deal with it (based on using 6.5-284 brass for 284), is to neck 6.5-->7-->.308, neck turn and cut into tge shoulder, then neck .308-->7mm.
Or....use bullets that don't seat deep enough to touch the donut.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines? </div></div>
Alpha mags don't really provide room for 2.985" COAL. Figure on ~2.965ish max.
That said, 7CM will fit standard short actions great.
On brass prep: it seems highly likely donuts will be encountered. Usually is when necking up. Best way I know to deal with it (based on using 6.5-284 brass for 284), is to neck 6.5-->7-->.308, neck turn and cut into tge shoulder, then neck .308-->7mm.
Or....use bullets that don't seat deep enough to touch the donut.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines? </div></div>
Alpha mags don't really provide room for 2.985" COAL. Figure on ~2.965ish max.
That said, 7CM will fit standard short actions great.
On brass prep: it seems highly likely donuts will be encountered. Usually is when necking up. Best way I know to deal with it (based on using 6.5-284 brass for 284), is to neck 6.5-->7-->.308, neck turn and cut into tge shoulder, then neck .308-->7mm.
Or....use bullets that don't seat deep enough to touch the donut. </div></div>
I simply stated length of the magazine, I know you can't load that long, I load all my 300WSM rounds to 2.955"
I wish it was easier to form the brass for this gun, but I'm still willing to try this round, what are the projected numbers with the 180gr. Bergers? I'm curious.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines? </div></div>
Alpha mags don't really provide room for 2.985" COAL. Figure on ~2.965ish max.
That said, 7CM will fit standard short actions great.
On brass prep: it seems highly likely donuts will be encountered. Usually is when necking up. Best way I know to deal with it (based on using 6.5-284 brass for 284), is to neck 6.5-->7-->.308, neck turn and cut into tge shoulder, then neck .308-->7mm.
Or....use bullets that don't seat deep enough to touch the donut. </div></div>
I simply stated length of the magazine, I know you can't load that long, I load all my 300WSM rounds to 2.955"
I wish it was easier to form the brass for this gun, but I'm still willing to try this round, what are the projected numbers with the 180gr. Bergers? I'm curious.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines? </div></div>
Alpha mags don't really provide room for 2.985" COAL. Figure on ~2.965ish max.
That said, 7CM will fit standard short actions great.
On brass prep: it seems highly likely donuts will be encountered. Usually is when necking up. Best way I know to deal with it (based on using 6.5-284 brass for 284), is to neck 6.5-->7-->.308, neck turn and cut into tge shoulder, then neck .308-->7mm.
Or....use bullets that don't seat deep enough to touch the donut. </div></div>what if you started with 30 t/c brass and then necked down to 7mm,would that eliminate the doughnut?the 6.5 creedmoor is based off of the 30 t/c right?same case?so how about necking down?i'm new to the necking up,necking down game.always shot standard calibers.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">I'm very curious to see how it performs with the 180gr. Berger hybrids, anyone have a velocity estimate? Also, would it be able to fit in a magazine with, lets say, 2.985" internal OAL like Alpha magazines? </div></div>
Alpha mags don't really provide room for 2.985" COAL. Figure on ~2.965ish max.
That said, 7CM will fit standard short actions great.
On brass prep: it seems highly likely donuts will be encountered. Usually is when necking up. Best way I know to deal with it (based on using 6.5-284 brass for 284), is to neck 6.5-->7-->.308, neck turn and cut into tge shoulder, then neck .308-->7mm.
Or....use bullets that don't seat deep enough to touch the donut. </div></div>what if you started with 30 t/c brass and then necked down to 7mm,would that eliminate the doughnut?the 6.5 creedmoor is based off of the 30 t/c right?same case?so how about necking down?i'm new to the necking up,necking down game.always shot standard calibers.
Re: 7mm creedmoor
Necking down is no problem, you're basically putting neck material back into the shoulder area. Necking up pulls thicker material from the shoulder area into the neck creating the doughnut.
No idea about the tc brass compatibility with the creedmoor.
Necking down is no problem, you're basically putting neck material back into the shoulder area. Necking up pulls thicker material from the shoulder area into the neck creating the doughnut.
No idea about the tc brass compatibility with the creedmoor.
Re: 7mm creedmoor
Well the creedmore is based on the TC necked down, correct? Then it should make sense that you could form 7mm creedmoor brass from it. That makes this much more viable for me, now I just need numbers to get me motivated into getting a barrel in this chamber
Well the creedmore is based on the TC necked down, correct? Then it should make sense that you could form 7mm creedmoor brass from it. That makes this much more viable for me, now I just need numbers to get me motivated into getting a barrel in this chamber
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? Then it should make sense that you could form 7mm creedmoor brass from it. That makes this much more viable for me, now I just need numbers to get me motivated into getting a barrel in this chamber </div></div>me too.wanting to try this caliber,just trying to find more info to see if it would be worth it.i like the 7mm bullet selection.i too would like to see more numbers to see if it's got any advantages over the 7-08.shorter case and steeper shoulders looks better if it can at least match or exceed the 7-08 numbers.i love the 6.5 creedmoor,just hopeing the 7mm version could be a little better.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? Then it should make sense that you could form 7mm creedmoor brass from it. That makes this much more viable for me, now I just need numbers to get me motivated into getting a barrel in this chamber
</div></div>me too.wanting to try this caliber,just trying to find more info to see if it would be worth it.i like the 7mm bullet selection.i too would like to see more numbers to see if it's got any advantages over the 7-08.shorter case and steeper shoulders looks better if it can at least match or exceed the 7-08 numbers.i love the 6.5 creedmoor,just hopeing the 7mm version could be a little better.Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? Then it should make sense that you could form 7mm creedmoor brass from it. That makes this much more viable for me, now I just need numbers to get me motivated into getting a barrel in this chamber </div></div>me too.wanting to try this caliber,just trying to find more info to see if it would be worth it.i like the 7mm bullet selection.i too would like to see more numbers to see if it's got any advantages over the 7-08.shorter case and steeper shoulders looks better if it can at least match or exceed the 7-08 numbers.i love the 6.5 creedmoor,just hopeing the 7mm version could be a little better. </div></div>
It will be. Any case that can launch a ~140gr 6.5 bullet at 2800+ is going to handle 162s at 2700+. That means a tick more drop, but a decent improvement in wind. It also provides better splash when you miss. 7mm rules.
A 162amax at 2900+ is a helluva performer.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? Then it should make sense that you could form 7mm creedmoor brass from it. That makes this much more viable for me, now I just need numbers to get me motivated into getting a barrel in this chamber
</div></div>me too.wanting to try this caliber,just trying to find more info to see if it would be worth it.i like the 7mm bullet selection.i too would like to see more numbers to see if it's got any advantages over the 7-08.shorter case and steeper shoulders looks better if it can at least match or exceed the 7-08 numbers.i love the 6.5 creedmoor,just hopeing the 7mm version could be a little better. </div></div>It will be. Any case that can launch a ~140gr 6.5 bullet at 2800+ is going to handle 162s at 2700+. That means a tick more drop, but a decent improvement in wind. It also provides better splash when you miss. 7mm rules.
A 162amax at 2900+ is a helluva performer.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? </div></div>
If this is correct then I guess we should be talking about a "7mm GPC" right?
Scope out this wiki link http://en.wikipedia.org/wiki/7mm_GPC
Says she can belch out a 168gr @ 2,972fps, Very intriguing cartridge!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? </div></div>
If this is correct then I guess we should be talking about a "7mm GPC" right?
Scope out this wiki link http://en.wikipedia.org/wiki/7mm_GPC
Says she can belch out a 168gr @ 2,972fps, Very intriguing cartridge!
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CrawDad338</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? </div></div>
If this is correct then I guess we should be talking about a "7mm GPC" right?
Scope out this wiki link http://en.wikipedia.org/wiki/7mm_GPC
Says she can belch out a 168gr @ 2,972fps, Very intriguing cartridge!
</div></div>
Interesting... According to the wiki specs, that IS simply a 6.5CM necked to 7, though wiki does not mention shoulder angle. 6.5CM and 7CM are both 30°…
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CrawDad338</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Well the creedmore is based on the TC necked down, correct? </div></div>
If this is correct then I guess we should be talking about a "7mm GPC" right?
Scope out this wiki link http://en.wikipedia.org/wiki/7mm_GPC
Says she can belch out a 168gr @ 2,972fps, Very intriguing cartridge!
</div></div>
Interesting... According to the wiki specs, that IS simply a 6.5CM necked to 7, though wiki does not mention shoulder angle. 6.5CM and 7CM are both 30°…
Re: 7mm creedmoor
Looks like it is the 7mm GPC, although I like the name 7mm Creedmoor better
2972fps is very good, Which means we are looking at a bit over 2900fps from a 26" barrel, which is how long I would plan to build it. It also means we should be able to achieve 2800fps from 180gr. bergers and still fit in a magazine.
I'm almost convinced, just need a little nudge, and a little cash to do it
Looks like it is the 7mm GPC, although I like the name 7mm Creedmoor better
2972fps is very good, Which means we are looking at a bit over 2900fps from a 26" barrel, which is how long I would plan to build it. It also means we should be able to achieve 2800fps from 180gr. bergers and still fit in a magazine.
I'm almost convinced, just need a little nudge, and a little cash to do it
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Looks like it is the 7mm GPC, although I like the name 7mm Creedmoor better
2972fps is very good, Which means we are looking at a bit over 2900fps from a 26" barrel, which is how long I would plan to build it. It also means we should be able to achieve 2800fps from 180gr. bergers and still fit in a magazine.
I'm almost convinced, just need a little nudge, and a little cash to do it </div></div>
Wanna split a reamer?
Nudge nudge...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rusty815</div><div class="ubbcode-body">Looks like it is the 7mm GPC, although I like the name 7mm Creedmoor better
2972fps is very good, Which means we are looking at a bit over 2900fps from a 26" barrel, which is how long I would plan to build it. It also means we should be able to achieve 2800fps from 180gr. bergers and still fit in a magazine.
I'm almost convinced, just need a little nudge, and a little cash to do it </div></div>
Wanna split a reamer?
Nudge nudge...
Re: 7mm creedmoor
I just dont see how, at least not at standard chamber pressures.
I just dont see how, at least not at standard chamber pressures.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">I just dont see how, at least not at standard chamber pressures. </div></div>
Valid point. I've been wondering this from the first time I heard 2900+(++) with 162amax.
My understanding on case capacity:
7CM - 53gr H2O
7mm-08 - 55gr
284 - 60.5 (measured myself)
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">I just dont see how, at least not at standard chamber pressures. </div></div>
Valid point. I've been wondering this from the first time I heard 2900+(++) with 162amax.
My understanding on case capacity:
7CM - 53gr H2O
7mm-08 - 55gr
284 - 60.5 (measured myself)
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">
Interesting... According to the wiki specs, that IS simply a 6.5CM necked to 7, though wiki does not mention shoulder angle. 6.5CM and 7CM are both 30°… </div></div>
I guess it's a matter of semantics, but if .30 T/C is the parent case I guess it would be a necked down .30 T/C. It would be WAY easier to neck down .30 T/C brass to .284 then it would be to expand the neck on a 6.5mm/.264 Creed case.
6.5mm creed is only pushing the 140 amax @ 2,820fps, I knew necking down a case you would lose some efficiency, just didn’t think it would be that much. 2,900fps is smoking for a 160ish grain projectile given the case size...
Is the case "design" the elephant in the room?
7mm "Creedmoor" is a much cooler sounding name...
30 bucks for 50 .30 T/C cases... http://www.manventureoutpost.com/products/Hornady-8663-30-TC-Unprimed-(Per-50).html
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">
Interesting... According to the wiki specs, that IS simply a 6.5CM necked to 7, though wiki does not mention shoulder angle. 6.5CM and 7CM are both 30°… </div></div>
I guess it's a matter of semantics, but if .30 T/C is the parent case I guess it would be a necked down .30 T/C. It would be WAY easier to neck down .30 T/C brass to .284 then it would be to expand the neck on a 6.5mm/.264 Creed case.
6.5mm creed is only pushing the 140 amax @ 2,820fps, I knew necking down a case you would lose some efficiency, just didn’t think it would be that much. 2,900fps is smoking for a 160ish grain projectile given the case size...
Is the case "design" the elephant in the room?
7mm "Creedmoor" is a much cooler sounding name...
30 bucks for 50 .30 T/C cases... http://www.manventureoutpost.com/products/Hornady-8663-30-TC-Unprimed-(Per-50).html
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">
My understanding on case capacity:
7CM - 53gr H2O
7mm-08 - 55gr
</div></div>
Must be case design...
http://www.chuckhawks.com/30_t-c_first_look.htm
From the read...
The .30 T/C is a short action (.308 length), rimless rifle cartridge that was developed for Thompson/Center by Hornady. It is a true .30 caliber cartridge with a case capacity slightly less than the .308 Winchester, which must make it very similar in size to Hornady's equally new, but rimmed, .308 Marlin Express. In fact, the .30 T/C looks much like a rimless version of Hornady's previously announced .308 Marlin. The promotional advertising for the two cartridges even sounds similar.
Hornady describes the new .30 T/C this way:
"Quite possibly the most technologically advanced cartridge ever developed, the new Hornady .30 T/C was specifically designed for Thompson Center's new Icon bolt-action rifle. Built on the premise of optimal ballistics, Hornady has perfected the balance between case volume, bore volume and burn rates for both the 150 and 165 grain offerings."
They further claim that the new cartridge, using their factory loaded 150 grain bullet, <span style="color: #FF0000">exceeds the muzzle velocity of the .308 Win. by 180 fps and the larger .30-06 by nearly 100 fps</span>. The also claim smooth feeding, full magazine capacity, a short bolt throw, longer barrel life, full ballistic potential in a short action case, and a 15% reduction in perceived recoil.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">
My understanding on case capacity:
7CM - 53gr H2O
7mm-08 - 55gr
</div></div>
Must be case design...
http://www.chuckhawks.com/30_t-c_first_look.htm
From the read...
The .30 T/C is a short action (.308 length), rimless rifle cartridge that was developed for Thompson/Center by Hornady. It is a true .30 caliber cartridge with a case capacity slightly less than the .308 Winchester, which must make it very similar in size to Hornady's equally new, but rimmed, .308 Marlin Express. In fact, the .30 T/C looks much like a rimless version of Hornady's previously announced .308 Marlin. The promotional advertising for the two cartridges even sounds similar.
Hornady describes the new .30 T/C this way:
"Quite possibly the most technologically advanced cartridge ever developed, the new Hornady .30 T/C was specifically designed for Thompson Center's new Icon bolt-action rifle. Built on the premise of optimal ballistics, Hornady has perfected the balance between case volume, bore volume and burn rates for both the 150 and 165 grain offerings."
They further claim that the new cartridge, using their factory loaded 150 grain bullet, <span style="color: #FF0000">exceeds the muzzle velocity of the .308 Win. by 180 fps and the larger .30-06 by nearly 100 fps</span>. The also claim smooth feeding, full magazine capacity, a short bolt throw, longer barrel life, full ballistic potential in a short action case, and a 15% reduction in perceived recoil.
Re: 7mm creedmoor
I'm NOT an experienced wildcatter, but I've dabbled...
In my experience, both necking up and down sucks - unless the chamber is designed for it.
Necking up brings the donuts, which you either have to ream out, or expand a bit oversize, neck turn, then neck to desired size.
Necking down makes necks thick - so they usually require turning...
In regard to "case design"...
I'm also no expert in interior ballistics...but it seems rather fantastical two cases, that outwardly appear VERY similar to one another, just that one is scaled up and has a 15% capacity advantage (7GPC vs 284), can ultimately have the same velocity potential.
I'm NOT an experienced wildcatter, but I've dabbled...
In my experience, both necking up and down sucks - unless the chamber is designed for it.
Necking up brings the donuts, which you either have to ream out, or expand a bit oversize, neck turn, then neck to desired size.
Necking down makes necks thick - so they usually require turning...
In regard to "case design"...
I'm also no expert in interior ballistics...but it seems rather fantastical two cases, that outwardly appear VERY similar to one another, just that one is scaled up and has a 15% capacity advantage (7GPC vs 284), can ultimately have the same velocity potential.
Re: 7mm creedmoor
I did a bunch of speed and accuracy testing with Mark last year before he sold the first rifle in 7 CM, in fact, the first one is labeled 7mm SAC if I remember right.
The 162's I was hitting 2800+ using Alliant 2000MR from a 24.9" barrel, the problem was I saw it shooting with a good deal of temp sensitivity.
H4350 was spitting 162's around 2725fps for a node but I did get a few rounds that shot past 2740fps without pressure issues.
The following are bullets/powders/speeds from my notes for the testing I did for Mark:
H4350
162 @ 2725 accurately
175 SMK @ 2680 accurately
180 Brg. Hybrid @ 2630 accurately
Varget was tested by Mark and he told me he was getting 162 Amax over 2880fps but then when he tried to recreate the test he was getting pressure problems and ruining brass with it.
I have heard through the grapevine that someone with a 7CM from Mark is shooting 162s a around 2890 with no pressure issues from a 26" barrel that has been through Melonite treatment.
It is a great round for the time that I shot it, I have plans to barrel into a 7CM after my current 6.5CM and extra 6.5 barrel are all burned up.
In my eyes, it is not a 284 replacement but it is a 7-08 replacement. The minute change (~4%) change in powder capacity for the longer neck and sharper shoulder coupled to a shorter trim length makes this a much more useful short action 7mm round than the 7-08. I really like this chambering a lot.
I did a bunch of speed and accuracy testing with Mark last year before he sold the first rifle in 7 CM, in fact, the first one is labeled 7mm SAC if I remember right.
The 162's I was hitting 2800+ using Alliant 2000MR from a 24.9" barrel, the problem was I saw it shooting with a good deal of temp sensitivity.
H4350 was spitting 162's around 2725fps for a node but I did get a few rounds that shot past 2740fps without pressure issues.
The following are bullets/powders/speeds from my notes for the testing I did for Mark:
H4350
162 @ 2725 accurately
175 SMK @ 2680 accurately
180 Brg. Hybrid @ 2630 accurately
Varget was tested by Mark and he told me he was getting 162 Amax over 2880fps but then when he tried to recreate the test he was getting pressure problems and ruining brass with it.
I have heard through the grapevine that someone with a 7CM from Mark is shooting 162s a around 2890 with no pressure issues from a 26" barrel that has been through Melonite treatment.
It is a great round for the time that I shot it, I have plans to barrel into a 7CM after my current 6.5CM and extra 6.5 barrel are all burned up.
In my eyes, it is not a 284 replacement but it is a 7-08 replacement. The minute change (~4%) change in powder capacity for the longer neck and sharper shoulder coupled to a shorter trim length makes this a much more useful short action 7mm round than the 7-08. I really like this chambering a lot.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">
The following are bullets/powders/speeds from my notes for the testing I did for Mark:
H4350
162 @ 2725 accurately
175 SMK @ 2680 accurately
180 Brg. Hybrid @ 2630 accurately
makes this a much more useful short action 7mm round than the 7-08. I really like this chambering a lot. </div></div>
Were the 180s Mag fed? I wonder how high we could get those 180's going with RL-17 through a 7mm Creed? If RL-17 and 208 amax work half ass in a .308 it might be worth a try...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">
The following are bullets/powders/speeds from my notes for the testing I did for Mark:
H4350
162 @ 2725 accurately
175 SMK @ 2680 accurately
180 Brg. Hybrid @ 2630 accurately
makes this a much more useful short action 7mm round than the 7-08. I really like this chambering a lot. </div></div>
Were the 180s Mag fed? I wonder how high we could get those 180's going with RL-17 through a 7mm Creed? If RL-17 and 208 amax work half ass in a .308 it might be worth a try...
Re: 7mm creedmoor
I know my thinking assumes ALOT but, this is how I look at it.
If we compare same projectile weights from similar calibers I see about 100 to 150 added by moving to the next size larger bore. So I would expect a 140 in the 7mm creedmoor to be moving at a respectable 2900-2950 maybe more with a long barrel. My reloading experience has suggested whenever I go up or down in bullet weight ~10 grains I will gain/loss somewhere around 70-80 fps in my 308. Using that same logic here I would guess the 162 would be moving ~2750-2800fps.
FWIW, I don’t believe in a magic case design.
I do believe in technology advances in powder designs which just so happened to come about when the 30 TC came out (“superformance” ring a bell?). Also, FWIW this same powder does the same thing in other factory loads other than the 30 TC.
I know my thinking assumes ALOT but, this is how I look at it.
If we compare same projectile weights from similar calibers I see about 100 to 150 added by moving to the next size larger bore. So I would expect a 140 in the 7mm creedmoor to be moving at a respectable 2900-2950 maybe more with a long barrel. My reloading experience has suggested whenever I go up or down in bullet weight ~10 grains I will gain/loss somewhere around 70-80 fps in my 308. Using that same logic here I would guess the 162 would be moving ~2750-2800fps.
FWIW, I don’t believe in a magic case design.
I do believe in technology advances in powder designs which just so happened to come about when the 30 TC came out (“superformance” ring a bell?). Also, FWIW this same powder does the same thing in other factory loads other than the 30 TC.
Re: 7mm creedmoor
Wow a lot happen in the last 20 minutes... guess I am slow.
Wow a lot happen in the last 20 minutes... guess I am slow.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">
I do believe in technology advances in powder designs which just so happened to come about when the 30 TC came out (“superformance” ring a bell?).
</div></div>
Good point, they're not discussing proprietary powders when making the .308 comparisons. It seems worth investigating further given the velocity claims, maybe they were using Reloader 17 on the 7mm GPC wiki entry.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">
I do believe in technology advances in powder designs which just so happened to come about when the 30 TC came out (“superformance” ring a bell?).
</div></div>
Good point, they're not discussing proprietary powders when making the .308 comparisons. It seems worth investigating further given the velocity claims, maybe they were using Reloader 17 on the 7mm GPC wiki entry.
Re: 7mm creedmoor
It seems to me that the 7mm Creedmoor likes faster burning powders, if varget can get over 2850fps then I suspect RL-15 might be able to get you where you want.
Also, case design could potentially cause such an increase in fps, just take a look at the 300WSM vs the 300WM. The 300WSM almost mirrors the 300WM speeds (albeit about 30-60fps less), and uses about 6-10gr. less powder. Since the TC has only 2gr. less powder capacity than the 308, it's safe to assume that the TC would have higher velocity, and the case design is to thank.
I also believe that the case design looses efficiency when necking down though, if the numbers are correct that is.
It seems to me that the 7mm Creedmoor likes faster burning powders, if varget can get over 2850fps then I suspect RL-15 might be able to get you where you want.
Also, case design could potentially cause such an increase in fps, just take a look at the 300WSM vs the 300WM. The 300WSM almost mirrors the 300WM speeds (albeit about 30-60fps less), and uses about 6-10gr. less powder. Since the TC has only 2gr. less powder capacity than the 308, it's safe to assume that the TC would have higher velocity, and the case design is to thank.
I also believe that the case design looses efficiency when necking down though, if the numbers are correct that is.
Re: 7mm creedmoor
ok,i think i'm.is mark barreling rifles for this yet?
ok,i think i'm.is mark barreling rifles for this yet?
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CrawDad338</div><div class="ubbcode-body">
Were the 180s Mag fed? I wonder how high we could get those 180's going with RL-17 through a 7mm Creed? If RL-17 and 208 amax work half ass in a .308 it might be worth a try... </div></div>
They were mag fed from an AICS 5rd single stack that did not have a front plate in it. With the front plate in there keeping rounds to 2.85-2.86 I "could" mag feed but there was ogive just inside the neck of the brass.
The 175 SMK mag feeds without issue at all. Considering the difference in BC (0.64 vs. 0.67) and the extra 50fps from the 175 SMK the performance tick ends up in favor of the 175SMK, there just isn't enough BC in the Berger to make up for the speed difference in drop and the wind difference is ~ 1/4MOA at 1000yd.
For the cost difference I can't see buying the Berger for this application... shooting 50% more of the 175SMK's and very likely your shooting skills will improve far more than that 1/4MOA on the 6.5MOA wind call.
<span style="font-weight: bold"><span style="text-decoration: underline">175SMK @ 0DA & 2680fps, 10mph full wind, 100yd zero</span></span>
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -321.9 -30.7 69.5 6.6
<span style="font-weight: bold"><span style="text-decoration: underline">180Hybrid @ 0DA & 2630fps, 10mph full wind, 100yd zero</span></span>
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -326.9 -31.2 66.7 6.4
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body">ok,i think i'm.is mark barreling rifles for this yet?
</div></div>
Yes he is.
I did not try any RL17 with the chambering again due to the behavior that RL17 is temp sensitive and Mark had asked me to look into an "all year 'round" setup so that only the atmospheric conditions mattered and the ammo temp variables were minimized.
I would expect that RL17 would show another 75fps+/- on the H4350 loads that I got such good repeatability with.
RL17 is also known to be pretty hard on barrels.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CrawDad338</div><div class="ubbcode-body">
Were the 180s Mag fed? I wonder how high we could get those 180's going with RL-17 through a 7mm Creed? If RL-17 and 208 amax work half ass in a .308 it might be worth a try... </div></div>
They were mag fed from an AICS 5rd single stack that did not have a front plate in it. With the front plate in there keeping rounds to 2.85-2.86 I "could" mag feed but there was ogive just inside the neck of the brass.
The 175 SMK mag feeds without issue at all. Considering the difference in BC (0.64 vs. 0.67) and the extra 50fps from the 175 SMK the performance tick ends up in favor of the 175SMK, there just isn't enough BC in the Berger to make up for the speed difference in drop and the wind difference is ~ 1/4MOA at 1000yd.
For the cost difference I can't see buying the Berger for this application... shooting 50% more of the 175SMK's and very likely your shooting skills will improve far more than that 1/4MOA on the 6.5MOA wind call.
<span style="font-weight: bold"><span style="text-decoration: underline">175SMK @ 0DA & 2680fps, 10mph full wind, 100yd zero</span></span>
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -321.9 -30.7 69.5 6.6
<span style="font-weight: bold"><span style="text-decoration: underline">180Hybrid @ 0DA & 2630fps, 10mph full wind, 100yd zero</span></span>
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -326.9 -31.2 66.7 6.4
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body">ok,i think i'm.is mark barreling rifles for this yet?
</div></div>
Yes he is.
I did not try any RL17 with the chambering again due to the behavior that RL17 is temp sensitive and Mark had asked me to look into an "all year 'round" setup so that only the atmospheric conditions mattered and the ammo temp variables were minimized.
I would expect that RL17 would show another 75fps+/- on the H4350 loads that I got such good repeatability with.
RL17 is also known to be pretty hard on barrels.
Re: 7mm creedmoor
Hey guys....I run a 7mmSAC (7mm Creedmoor) built by Mark at Short Action Customs. Mark provided the dies and I went to loading.
I run Hornady 162gr A-Max with 41gr of 8208 XBR righ at 2900 fps. I sized all of the 6.5 brass with minimal evidence of a doughnut. I was running 41.5gr at 2950 fps but felt the added pressure wasn't necessary.
I promised Mark I would do a write-up of the rifle but just haven't got around to it. I promise I will do it asap. ;-) One of the main reasons is I don't have a 5 shot group pic yet. Rifle details and more will be in the other thread soon.
Hey guys....I run a 7mmSAC (7mm Creedmoor) built by Mark at Short Action Customs. Mark provided the dies and I went to loading.
I run Hornady 162gr A-Max with 41gr of 8208 XBR righ at 2900 fps. I sized all of the 6.5 brass with minimal evidence of a doughnut. I was running 41.5gr at 2950 fps but felt the added pressure wasn't necessary.
I promised Mark I would do a write-up of the rifle but just haven't got around to it. I promise I will do it asap. ;-) One of the main reasons is I don't have a 5 shot group pic yet. Rifle details and more will be in the other thread soon.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RODENT</div><div class="ubbcode-body">
I run Hornady 162gr A-Max with 41gr of 8208 XBR righ at 2900 fps. I sized all of the 6.5 brass with minimal evidence of a doughnut. I was running 41.5gr at 2950 fps but felt the added pressure wasn't necessary.
</div></div>
I was skeptical about the velocity claims at 1st when I seen this thread, but after reading the 7mm GPC wiki entry and watching posters with 1st hand knowledge, there are just too many reports of a .284/160gr going near 2,900fps to call BS. This is awesome, ballistic twin of a 7mm-08 (maybe better) that can mag load the long high BC pills in a short action! WooHoo!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RODENT</div><div class="ubbcode-body">
I run Hornady 162gr A-Max with 41gr of 8208 XBR righ at 2900 fps. I sized all of the 6.5 brass with minimal evidence of a doughnut. I was running 41.5gr at 2950 fps but felt the added pressure wasn't necessary.
</div></div>
I was skeptical about the velocity claims at 1st when I seen this thread, but after reading the 7mm GPC wiki entry and watching posters with 1st hand knowledge, there are just too many reports of a .284/160gr going near 2,900fps to call BS. This is awesome, ballistic twin of a 7mm-08 (maybe better) that can mag load the long high BC pills in a short action! WooHoo!
Re: 7mm creedmoor
I was waiting to see when Rodent would pop in here..
I was waiting to see when Rodent would pop in here..
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RODENT</div><div class="ubbcode-body">Hey guys....I run a 7mmSAC (7mm Creedmoor) built by Mark at Short Action Customs. Mark provided the dies and I went to loading.
I run Hornady 162gr A-Max with 41gr of 8208 XBR righ at 2900 fps. I sized all of the 6.5 brass with minimal evidence of a doughnut. I was running 41.5gr at 2950 fps but felt the added pressure wasn't necessary.
I promised Mark I would do a write-up of the rifle but just haven't got around to it. I promise I will do it asap. ;-) One of the main reasons is I don't have a 5 shot group pic yet. Rifle details and more will be in the other thread soon.
</div></div>
That is spectacular, as I suspected the 7mm Creedmor/GPC/SAC loves faster burning powder. When you do the write up, I would be happy to read it.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RODENT</div><div class="ubbcode-body">Hey guys....I run a 7mmSAC (7mm Creedmoor) built by Mark at Short Action Customs. Mark provided the dies and I went to loading.
I run Hornady 162gr A-Max with 41gr of 8208 XBR righ at 2900 fps. I sized all of the 6.5 brass with minimal evidence of a doughnut. I was running 41.5gr at 2950 fps but felt the added pressure wasn't necessary.
I promised Mark I would do a write-up of the rifle but just haven't got around to it. I promise I will do it asap. ;-) One of the main reasons is I don't have a 5 shot group pic yet. Rifle details and more will be in the other thread soon.
</div></div>
That is spectacular, as I suspected the 7mm Creedmor/GPC/SAC loves faster burning powder. When you do the write up, I would be happy to read it.
Re: 7mm creedmoor
Bohem's data seems more inline with what i would expect
however melonite barrels have been shown in numerous instances to allow for substantial gains in performance
Rodents info is interesting
is fps data from chrono, if so then that maybe issue
or is data reverse calc based on actual dope used?
So as long as the XC case has been around, why no 7XC?
the BR crowd wildcat anything that's gives them an advantage.
I remain a skeptic until more data is available.
Melonite maybe the X factor
Bohem's data seems more inline with what i would expect
however melonite barrels have been shown in numerous instances to allow for substantial gains in performance
Rodents info is interesting
is fps data from chrono, if so then that maybe issue
or is data reverse calc based on actual dope used?
So as long as the XC case has been around, why no 7XC?
the BR crowd wildcat anything that's gives them an advantage.
I remain a skeptic until more data is available.
Melonite maybe the X factor
Re: 7mm creedmoor
Jedi
My barrel is melonited and I do agree that is a major contributing factor. I think you also need to consider barrel length, grooves etc. I believe the MOST important factor of my data is the powder. I stumbled onto it trying to find something close to the new cartridge. The Hodgdon site had it listed within the 7mm-08 load data. I bought a pound and tried it. The data was so good I bought 16 lbs., so I'm committed.
The ballistic data is based on actual targets being engaged and applying the data to my shooter app and exbal. The two seem to be matching throughout the scale. I have only been able to engage targets out to 700 yds to verify accuracy so far. I plan on heading to Young's Longshot this coming Monday and capture the good stuff for everyone.
I can't forget the superb craftmanship that went into this rifle. Mark (Short Action Customs) is one busy guy but still managed to build a nice rig. I have since swapped the stock from an A5 to a McCree so I have more work to do. Like I said, full report to follow SOON.
RODENT
Jedi
My barrel is melonited and I do agree that is a major contributing factor. I think you also need to consider barrel length, grooves etc. I believe the MOST important factor of my data is the powder. I stumbled onto it trying to find something close to the new cartridge. The Hodgdon site had it listed within the 7mm-08 load data. I bought a pound and tried it. The data was so good I bought 16 lbs., so I'm committed.
The ballistic data is based on actual targets being engaged and applying the data to my shooter app and exbal. The two seem to be matching throughout the scale. I have only been able to engage targets out to 700 yds to verify accuracy so far. I plan on heading to Young's Longshot this coming Monday and capture the good stuff for everyone.
I can't forget the superb craftmanship that went into this rifle. Mark (Short Action Customs) is one busy guy but still managed to build a nice rig. I have since swapped the stock from an A5 to a McCree so I have more work to do. Like I said, full report to follow SOON.
RODENT
Re: 7mm creedmoor
Hodgdon website shows IMR 8208 XBR as the fastest powder for 7mm-08 and 162 Amax" by a good bit, 2,725fps max load. I assume that's a 24'' test barrel.
Is that a clean burning powder?
Hodgdon website shows IMR 8208 XBR as the fastest powder for 7mm-08 and 162 Amax" by a good bit, 2,725fps max load. I assume that's a 24'' test barrel.
Is that a clean burning powder?
Re: 7mm creedmoor
tag
tag
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CrawDad338</div><div class="ubbcode-body">Hodgdon website shows IMR 8208 XBR as the fastest powder for 7mm-08 and 162 Amax" by a good bit, 2,725fps max load. I assume that's a 24'' test barrel.
Is that a clean burning powder? </div></div>
The first couple patches are very black. Beyond that its all good. 4-5 to clean totally.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CrawDad338</div><div class="ubbcode-body">Hodgdon website shows IMR 8208 XBR as the fastest powder for 7mm-08 and 162 Amax" by a good bit, 2,725fps max load. I assume that's a 24'' test barrel.
Is that a clean burning powder? </div></div>
The first couple patches are very black. Beyond that its all good. 4-5 to clean totally.
Re: 7mm creedmoor
tag
tag
Re: 7mm creedmoor
Hey Guys, I figured its time for me to drop in.
I came up with the idea of doing the 7mm Creedmoor middle last year while checking out some Corbon 7mm-08 Performance Match ammo with a 168 bullet shoved deep inside the case. I have always been a big fan of the 6.5 Creedmoor's straighter body, 30 Degree shoulder and longer neck than the 260, so I started seating bullets and making dummies.
The first rifle I build used a 7mm barrel that used a 6.5 Creedmoor chamber reamer. Then I necked it to .317, then throated it out for a COAL of 2.855" ish with a 162 A-Max. That rifle went to Bohem for testing as I just did not have the time.
Until reading this thread I never heard of the 7mm GPC, as my idea was taking a 6.5 Creedmoor and necking it up. I only used the "7mm SAC" because that is what my stencil for etching said, now I just call it the 7mm Creedmoor.
To date there are only 4 7mm Creedmoor rifles barreled up in our shop, one is still in our possession waiting pickup. For best performance, we suggest 26" barrel lengths, Melonite is always a good idea.
Faster burning powders are the way to go. Initial testing was done with H4350 and was way to slow. Then Varget was used and we stuffed almost 47 Gr in the case, so that was no good. Then Bohem and others used much faster powders and it found its home there.
Overall, the goal I was trying to accomplish with the 7mm Creedmoor was a cartridge that would compete/exceed the performance of the 260/6.5 Creedmoor while bucking the wind better, and increasing barrel life. I would say inherit accuracy was another important benefit as all the rifles are just extremely accurate.
We now have our own 7mm Creedmoor reamer that has our freebore and neck specs that seems to work well. We have been modifying Redding die sets with new 7mm Sizing Stem assemblies and opening up certain parts of the die. Its a very easy cartridge to work with and I honestly like Hornady 6.5 Creedmoor brass. If you measure the H2O capacity, its typically close to the same consistency as Lapua.
I'm planning on doing more builds and some personal barrels for more testing. Chances are these barrels/rifles will be sent out for testing by other people who have more time than I do!!!!
Mark
Hey Guys, I figured its time for me to drop in.
I came up with the idea of doing the 7mm Creedmoor middle last year while checking out some Corbon 7mm-08 Performance Match ammo with a 168 bullet shoved deep inside the case. I have always been a big fan of the 6.5 Creedmoor's straighter body, 30 Degree shoulder and longer neck than the 260, so I started seating bullets and making dummies.
The first rifle I build used a 7mm barrel that used a 6.5 Creedmoor chamber reamer. Then I necked it to .317, then throated it out for a COAL of 2.855" ish with a 162 A-Max. That rifle went to Bohem for testing as I just did not have the time.
Until reading this thread I never heard of the 7mm GPC, as my idea was taking a 6.5 Creedmoor and necking it up. I only used the "7mm SAC" because that is what my stencil for etching said, now I just call it the 7mm Creedmoor.
To date there are only 4 7mm Creedmoor rifles barreled up in our shop, one is still in our possession waiting pickup. For best performance, we suggest 26" barrel lengths, Melonite is always a good idea.
Faster burning powders are the way to go. Initial testing was done with H4350 and was way to slow. Then Varget was used and we stuffed almost 47 Gr in the case, so that was no good. Then Bohem and others used much faster powders and it found its home there.
Overall, the goal I was trying to accomplish with the 7mm Creedmoor was a cartridge that would compete/exceed the performance of the 260/6.5 Creedmoor while bucking the wind better, and increasing barrel life. I would say inherit accuracy was another important benefit as all the rifles are just extremely accurate.
We now have our own 7mm Creedmoor reamer that has our freebore and neck specs that seems to work well. We have been modifying Redding die sets with new 7mm Sizing Stem assemblies and opening up certain parts of the die. Its a very easy cartridge to work with and I honestly like Hornady 6.5 Creedmoor brass. If you measure the H2O capacity, its typically close to the same consistency as Lapua.
I'm planning on doing more builds and some personal barrels for more testing. Chances are these barrels/rifles will be sent out for testing by other people who have more time than I do!!!!
Mark
Re: 7mm creedmoor
thanks for the info mark.just as soon as i find a barrel you will have the chance to build your first 7 creedmoor gas gun.i'm excited.
thanks for the info mark.just as soon as i find a barrel you will have the chance to build your first 7 creedmoor gas gun.i'm excited.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body">thanks for the info mark.just as soon as i find a barrel you will have the chance to build your first 7 creedmoor gas gun.i'm excited.
</div></div>
Me too! That was going to be my next project. That is something I wait to read about.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnnyDL</div><div class="ubbcode-body">thanks for the info mark.just as soon as i find a barrel you will have the chance to build your first 7 creedmoor gas gun.i'm excited.
</div></div>
Me too! That was going to be my next project. That is something I wait to read about.
Re: 7mm creedmoor
I'm going to build a 257 Creedmoor and a 270 Creedmoor. Both are better than the 6, 6.5 and 7. Combined.
I'm going to build a 257 Creedmoor and a 270 Creedmoor. Both are better than the 6, 6.5 and 7. Combined.
Re: 7mm creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">Considering the difference in BC (0.64 vs. 0.67) and the extra 50fps from the 175 SMK the performance tick ends up in favor of the 175SMK, there just isn't enough BC in the Berger to make up for the speed difference in drop and the wind difference is ~ 1/4MOA at 1000yd.
For the cost difference I can't see buying the Berger for this application... shooting 50% more of the 175SMK's and very likely your shooting skills will improve far more than that 1/4MOA on the 6.5MOA wind call.
175SMK @ 0DA & 2680fps, 10mph full wind, 100yd zero
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -321.9 -30.7 69.5 6.6
180Hybrid @ 0DA & 2630fps, 10mph full wind, 100yd zero
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -326.9 -31.2 66.7 6.4 </div></div>
I hear ya on projectile cost differences and shooting time...
Did Sierra come out with a new 175? If so a G1 of .640 is pretty darn nice for the price.
Here's what they still have listed on their website... http://www.sierrabullets.com/index.cfm?s...mp;bullettype=0
.608 @ 2100 fps and above
.582 between 2100 and 1530 fps
.532 between 1530 and 1300 fps
.500 @ 1300 fps and below
Food for thought: Berger rates their BC over a longer distance or "avg BC" where Sierra uses a stepped G1 method. Using Sierra Max BC for a full 1,000 yards wouldn't be an honest comparison. I try to stick to the G7s when the data is available.
I'm hoping we can squeeze out another 100fps from your 175gr and 180gr figures with 8208 XBR and a 26'' barrel, that would keep them supersonic for 1,440 and 1,480 yards respectively using Litz corrected G7 profiles : )
The amax 162s @ 2,900 are supersonic for 1,430 yards...I will probably go this route for cost effectiveness. Anyone know if this particular Amax is stable at transonic speeds out of a 8 twist?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">Considering the difference in BC (0.64 vs. 0.67) and the extra 50fps from the 175 SMK the performance tick ends up in favor of the 175SMK, there just isn't enough BC in the Berger to make up for the speed difference in drop and the wind difference is ~ 1/4MOA at 1000yd.
For the cost difference I can't see buying the Berger for this application... shooting 50% more of the 175SMK's and very likely your shooting skills will improve far more than that 1/4MOA on the 6.5MOA wind call.
175SMK @ 0DA & 2680fps, 10mph full wind, 100yd zero
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -321.9 -30.7 69.5 6.6
180Hybrid @ 0DA & 2630fps, 10mph full wind, 100yd zero
Range Drop Drop Windage Windage
(yd) (in) (MOA) (in) (MOA)
1000 -326.9 -31.2 66.7 6.4 </div></div>
I hear ya on projectile cost differences and shooting time...
Did Sierra come out with a new 175? If so a G1 of .640 is pretty darn nice for the price.
Here's what they still have listed on their website... http://www.sierrabullets.com/index.cfm?s...mp;bullettype=0
.608 @ 2100 fps and above
.582 between 2100 and 1530 fps
.532 between 1530 and 1300 fps
.500 @ 1300 fps and below
Food for thought: Berger rates their BC over a longer distance or "avg BC" where Sierra uses a stepped G1 method. Using Sierra Max BC for a full 1,000 yards wouldn't be an honest comparison. I try to stick to the G7s when the data is available.
I'm hoping we can squeeze out another 100fps from your 175gr and 180gr figures with 8208 XBR and a 26'' barrel, that would keep them supersonic for 1,440 and 1,480 yards respectively using Litz corrected G7 profiles : )
The amax 162s @ 2,900 are supersonic for 1,430 yards...I will probably go this route for cost effectiveness. Anyone know if this particular Amax is stable at transonic speeds out of a 8 twist?
Re: 7mm creedmoor
I think ~.61 is a more accurate G1 number for the 175smk. The 180smk is a solid improvement over it at ~.65, and of course, .67 for the Berger 180 hybrid.
I suspect the highest performance in this cartridge will come from the 168 Berger. I've run the numbers a million times for my 284, which can hit 2825 with a 180, 2925 with the 168, and 2950 with the 162. Honestly, out to 1000, there is little difference between any of them, the 16X bullets being a bit flatter, the 180 a shade less drift. It's not till 1100+ the 180 takes over...and its not by a lot over the 162. Even less advantage over the 168.
That all said, all things considered, the 162 is really the pick of the litter. Very, very good bullet, and cheap.
I think ~.61 is a more accurate G1 number for the 175smk. The 180smk is a solid improvement over it at ~.65, and of course, .67 for the Berger 180 hybrid.
I suspect the highest performance in this cartridge will come from the 168 Berger. I've run the numbers a million times for my 284, which can hit 2825 with a 180, 2925 with the 168, and 2950 with the 162. Honestly, out to 1000, there is little difference between any of them, the 16X bullets being a bit flatter, the 180 a shade less drift. It's not till 1100+ the 180 takes over...and its not by a lot over the 162. Even less advantage over the 168.
That all said, all things considered, the 162 is really the pick of the litter. Very, very good bullet, and cheap.
Re: 7mm creedmoor
Any early reports on brass life with the 'warmer' loads? I've seen primer pockets open up surprisingly quickly on 6.5 CM brass running H123A-Max bullets @ a tick over 3000fps... so I'm a little leery of loads that purport to push a 7mm 162gn bullet even close to that speed. If the case life *is* holding up... then I better hurry up and shoot out my 6.5CM to give me an excuse to re-barrel
Any early reports on brass life with the 'warmer' loads? I've seen primer pockets open up surprisingly quickly on 6.5 CM brass running H123A-Max bullets @ a tick over 3000fps... so I'm a little leery of loads that purport to push a 7mm 162gn bullet even close to that speed. If the case life *is* holding up... then I better hurry up and shoot out my 6.5CM to give me an excuse to re-barrel
