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300 PRC update

Are you using a comparator before and after sizing? I assume so if you are measuring your bump. Are the cases growing back exactly the same amount each time?
thanks davethedog, I do use a comparator. My brass is going on it's second firing, I only size the neck on new brass and then bump the shoulder back .002 there after. I haven't taken any shoulder measurements on the twice fired brass yet but will and report back with the once and twice fire brass shoulder measurements.
 
Just got in from testing some 245gr Berger EOL's. I'll say...I set them up to fail...and they didn't. Here is the process I went through.

I loaded the 245's to the same powder charge of my 230 A-Tips. The Bergers are of course 15 grains heavier....just a smidge longer...but the bearing surface is really close. Percentage wise...there isn't that much difference in the rear geometery. Ok....so I just stuck some powder in...and then I seated these long ass bullets without changing my seating stem....and they are barely CIP Length magazine capable.

Shot a 5 round control group with the 230gr A-Tips.... 1/2" group with a speed averageing 2880fps. Shot a group of Bergers.... 2860fps...1/2" group.....this is on a 32F and raining day! Gotta like that. I removed the MagnetoSpeedV3 and moved my barrel tuner from the '4' setting to the '0' setting....I was also shooting for the very first time a new Area 419 Sidewinder Magnum brake...so that could alter the harmonics slightly. Dialed to '0' and shot a .477" group....I'll call it a day.

Almost zero load development. I'll take some of the 245's to TVP when I can...stretch them out to a mile and true the BC in my calc. For the $20-$30 lower price point than the 230gr A-Tips....as long as they are close...I'll probably switch over to the Bergers...but...but...I need to test them in the spring when the weather warms up and I want to load them longer...single feed...and get the speeds up to above 2950fps....but awaiting the Lapua brass before I start getting crazy again.

All in all it was a good day...I would post pics...but the wetness tore the targets...they were stapled to plastic backers and they were glued to them with the water....no special groups...nothing tiny...but some good solid 1/2" groups. Was also working with the Pheonix Bipod....I still gotta learn to not try to load the bipod....it simply moves away from you on a bench....my groups could have been epic...but I was getting vertical from inconsistent.....well...everything. Next time...I'll probably take the Atlas.

More data for the 245's in a week or so....at distance.
 
Midsouth has Hornady 300 PRC brass in stock as of this post.

I got the update on Discord that this brass was available....I ordered 100 pieces for a friend of mine who traveling today...and oblivious I just bought him some brass....I'm sure he will be excited...especially for that price......his 300PRC will be here in a month or so.
 
I'm noticing a disturbing trend, factory H225 that was $38 a box, went to $45 a while back. Now I'm seeing it advertised at $60 a box even though it's not in stock and no backorders. Man, I hope the factory stuff isn't going to be $60 a box, I always like to keep some around, but geeeeeeezus.
 
I'm noticing a disturbing trend, factory H225 that was $38 a box, went to $45 a while back. Now I'm seeing it advertised at $60 a box even though it's not in stock and no backorders. Man, I hope the factory stuff isn't going to be $60 a box, I always like to keep some around, but geeeeeeezus.

Sportsman's Warehouse in N. KY had two boxes of 225 ELD-M ammo.... $54.99/ea....friend bought both.
 
Are you using a comparator before and after sizing? I assume so if you are measuring your bump. Are the cases growing back exactly the same amount each time?

Measured up some of the Hornady and ADG brass, unfortunately I didn’t have an unfired Hornady brass to measure. Rather interesting to look at the brass growth progression of the brass. Measurements were taken using a Whidden shoulder comparator which from memory measures at the .420 area of the shoulder.
The ADG brass first, from new to once fired there was .006 growth (2.183 to 2.189) from once fired to twice fired there was .003 growth (2.189 to 2.192).
On the Hornady brass from once fired to twice fired there was .004 growth (2.188 to 2.192).
So after the first firing there is only .001 difference between the difference brass and after the second firing both measure the same .
Not sure what all this means but looking forward to feedback.
 
Just got in from testing some 245gr Berger EOL's. I'll say...I set them up to fail...and they didn't. Here is the process I went through.

I loaded the 245's to the same powder charge of my 230 A-Tips. The Bergers are of course 15 grains heavier....just a smidge longer...but the bearing surface is really close. Percentage wise...there isn't that much difference in the rear geometery. Ok....so I just stuck some powder in...and then I seated these long ass bullets without changing my seating stem....and they are barely CIP Length magazine capable.

Shot a 5 round control group with the 230gr A-Tips.... 1/2" group with a speed averageing 2880fps. Shot a group of Bergers.... 2860fps...1/2" group.....this is on a 32F and raining day! Gotta like that. I removed the MagnetoSpeedV3 and moved my barrel tuner from the '4' setting to the '0' setting....I was also shooting for the very first time a new Area 419 Sidewinder Magnum brake...so that could alter the harmonics slightly. Dialed to '0' and shot a .477" group....I'll call it a day.

Almost zero load development. I'll take some of the 245's to TVP when I can...stretch them out to a mile and true the BC in my calc. For the $20-$30 lower price point than the 230gr A-Tips....as long as they are close...I'll probably switch over to the Bergers...but...but...I need to test them in the spring when the weather warms up and I want to load them longer...single feed...and get the speeds up to above 2950fps....but awaiting the Lapua brass before I start getting crazy again.

All in all it was a good day...I would post pics...but the wetness tore the targets...they were stapled to plastic backers and they were glued to them with the water....no special groups...nothing tiny...but some good solid 1/2" groups. Was also working with the Pheonix Bipod....I still gotta learn to not try to load the bipod....it simply moves away from you on a bench....my groups could have been epic...but I was getting vertical from inconsistent.....well...everything. Next time...I'll probably take the Atlas.

More data for the 245's in a week or so....at distance.

Stop doing stuff that is going to make me do stuff...

I have a few hundred 245s sitting on the shelf that I haven't wanted to screw with. I guess I have to now.
 
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Just ordered a Savage Elite Precision in 300 PRC
Savage Elite Precision
I have Hornady brass, some Ramshot Magnum and some H1000 and just ordered:
Berger Long Range Hybrid Target Bullets 30 Caliber (308 Diameter) 220 Grain Hollow
I also have some Hornady bullets and am thinking about getting some A-Tips (expensive)


I need to order a die set and am wondering what the current consensus is on best die set is for this round?
I saw the post above about the Redding dies, so looking at that but am wondering about other die options?

Thanks!
 
Just ordered a Savage Elite Precision in 300 PRC
Savage Elite Precision
I have Hornady brass, some Ramshot Magnum and some H1000 and just ordered:
Berger Long Range Hybrid Target Bullets 30 Caliber (308 Diameter) 220 Grain Hollow
I also have some Hornady bullets and am thinking about getting some A-Tips (expensive)


I need to order a die set and am wondering what the current consensus is on best die set is for this round?
I saw the post above about the Redding dies, so looking at that but am wondering about other die options?

Thanks!
Can’t speak to anything other than the Redding but they have been sizing for me very well. On a Sinclair gauge I’m getting about .5-1 thou runout which is acceptable for me.
 
Thanks!
Any other ideas on dies?
I'd get the Redding or at this point any other die because I cannot find any 300 PRC dies in stock anywhere?
Any suggestions on where I might find dies in stock?
Thanks!
 
Thanks!
Any other ideas on dies?
I'd get the Redding or at this point any other die because I cannot find any 300 PRC dies in stock anywhere?
Any suggestions on where I might find dies in stock?
Thanks!
I scored the last set from accurate arms and ammo, those guys are pretty nice. Luckily if you’ve got new brass, all you’ll need is an expander die to get started. Many people have good luck with the Hornady bushing dies as well. May be easier to come by given that it’s a Hornady cartridge.

If you can’t find anything I don’t mind sizing them up for you while you hunt for some. I know that’s weird but it’s a genuine offer.
 
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Thanks!
Any other ideas on dies?
I'd get the Redding or at this point any other die because I cannot find any 300 PRC dies in stock anywhere?
Any suggestions on where I might find dies in stock?
Thanks!
I have been waiting two months for my Redding dies, should be two more weeks and the 300 PRC dies will hit the market again.
 
I scored the last set from accurate arms and ammo, those guys are pretty nice. Luckily if you’ve got new brass, all you’ll need is an expander die to get started. Many people have good luck with the Hornady bushing dies as well. May be easier to come by given that it’s a Hornady cartridge.

If you can’t find anything I don’t mind sizing them up for you while you hunt for some. I know that’s weird but it’s a genuine offer.
Yeah cool bro. I'm OK though I'll just wait. I've got a 6.5 PRC to keep me busy for now. I have dies and supplies for that.
Thanks.
 
Thanks!
Any other ideas on dies?
I'd get the Redding or at this point any other die because I cannot find any 300 PRC dies in stock anywhere?
Any suggestions on where I might find dies in stock?
Thanks!
L.E. Wilson bushing bump dies are 👍.

Bruno's has one
 
Thanks!
Any other ideas on dies?
I'd get the Redding or at this point any other die because I cannot find any 300 PRC dies in stock anywhere?
Any suggestions on where I might find dies in stock?
Thanks!
Try L.E. Wilson they have a full length bushing die that works really great for me.
 
So I got an in stock notification from Midway and picked up an RCBS Match Master die set.

Ordered a couple of days ago.

I just looked again and they are already out of stock.

Anyway I got a set so time to work up some loads.
 
Thanks!
Any other ideas on dies?
I'd get the Redding or at this point any other die because I cannot find any 300 PRC dies in stock anywhere?
Any suggestions on where I might find dies in stock?
Thanks!
I've got the Redding neck bushing die, full length die with neck bushing & Comp seater. Thumbs up on all three of those Redding dies. Also have the Wilson arbor press seating die. Limited testing has shown the Wilson to have lower concentricity and lower variation in base-to-ogive. I've got a Whidden set I plan to put up for sale.
 
I bought a 8 twist barrel and then I had second thoughts. I ordered a second barrel in 10 twist. Now I can sleep at night knowing I have it covered.
Been reading this thread. How'd this work out for you? I have a gain twist ordered, 1-9 to 1-8, but I will mostly shoot monolithic bullets.
 
I've got the Redding neck bushing die, full length die with neck bushing & Comp seater. Thumbs up on all three of those Redding dies. Also have the Wilson arbor press seating die. Limited testing has shown the Wilson to have lower concentricity and lower variation in base-to-ogive. I've got a Whidden set I plan to put up for sale.
Let me know when / if you want to sell that Whidden set.
Why are you selling? I thought these were good dies?
 
Just scored 8lbs of VV570. Was hesitant to get that much but it sounds like it should work well with the 245s.
I called Berger before I made the purchase (they put it on hold for me) to check before buying so much without testing and he said I shouldn't be on the phone with him but rather putting the order in for the powder LOL
My favorite powder of all time. been using it for over 15 years.
 
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Let me know when / if you want to sell that Whidden set.
Why are you selling? I thought these were good dies?

I think they are good, but I've loaded ~100 with the Redding dies and 50 with the Whiddens. Reddings had more consistent BTO and concentricity.
 
Thank you for the awesome data!
Any signs of excessive pressure?

I started to do some load development with them, but decided to go with the 230s. I didn't notice a huge difference in torque, but I didn't spend a ton of time with them. I was pretty rushed that week.

I did some prelim work on your wildcat (I hope you appreciate the name). GRT says it can push the 250s at 3120 fps with 124 grains of N570 :)

View attachment 7435646
What software is this a screen shot from?
 
Been following this 300 PRC thread for a while.

I have a 26” CF Bartlein Barrel on order (since the end of June...) with a 9.5 twist rate. I am a hunter, but shoot at steel a fair amount (~2000 rounds per year) out to 1300 m. The 300 prc was bought ostensibly for elk, but that tends to be 1 week a year, leaving steel for the other 51 weeks.

I plan on mostly shooting 205 gr Berger Hybrid hunting rounds, but I like to test out different bullets and loads. I will probably stick to Bergers as I have had really good luck with them out of my 260 Rem, but I like to experiment.

I also load pretty conservatively, so I won’t be getting anything close to 3000 fps+ with heavier bullets.

So my question is whether you think the 9.5 twist rate will work well for what I want. It seems to stabilize well up to 220 gr, but then become marginal at more bullet weight.

Earlier I saw that Dave Tooley was going with 9.5, so that is reassuring, but this is my first “custom” rifle, and I don’t want to mess it up.
I'm waiting on parts for a 300 PRC with similar hunting/target ambitions. Has anyone here tried the Hammer bullets in a 300 PRC? Thinking the 199 or 214 grain bullets.
 
Gordon’s Reloading Tool. It’s a modern replacement for QuickLoad, vastly superior. Free, but if you contribute via Patreon you get more updates and tech support.
What software is this a screen shot from?
 
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So, we all know that ammo for the 300PRC is scare in the market place. We also know that finding reloading components have been frustratingly scarce as well. Powders hit websites and are sold out in mere seconds. Same with primers, bullets and brass. With ADG not planning to come to market with more 300PRC brass until months from now, and the Lapua release that may get back up into summer, what exactly are we to do? Buy Hornady brass? Have you tried finding that lately? It has been gobbled up off the market as well. With competition season approaching, many people are getting nervous about not having anything. I myself have lowered my powder loads on my 230gr A-Tips and my new 245gr EOL's just to baby my brass so it will last longer.

Well, let me give you an alternative. Just incase the brass of ADG and Lapua get pushed back to a point that makes it to where you can't shoot, let's walk through one of the simplest brass resizing/substitution jobs you will ever encounter. I'll walk through how to turn 375 Ruger brass into 300 PRC. Yes, going from the parent to the child case. After this you will see how simple it is, and you will see that it wasn't much innovation to take the 375 Ruger to the 300 PRC. Wildcatters did it first and Hornady just SAAMI spec'd it and called it Easy Money. The cartridge is my current favorite for 1000 to 2000 yards...and slightly beyond. Now...let's take a look.

So, I'm using my normal full length sizing die with the expander ball removed...I never run an expander ball. I'm using a 334 bushing. I would not use a non-bushing die because it squeezes down too small. I did not find it necessary to go bigger and do two or more sizing operations making the neck smaller each time. I did however only partially size in a few steps pushing the neck in and the shoulder back. Let's take a look:

375_1.png


The 375 Ruger next to the 300PRC. You will notice that the cases are really close in OAL. You will notice that the 375 neck is much higher up and the shoulder angle is different. Everything else is very close, like body taper. So, I sprayed everything with Hornady One Shot and let dry. Next I attacked only half of the neck.

375_3.png


You will notice I only did a partial neck sizing. Look how the brass being squeezed in for the new neck diameter and flowing down. I only did a partial size here, lifted the handle...and then gently went for the remainder of just the neck.

375_4.png


Neck is done, but we haven't attacked that shoulder yet. What I do here is to slowly push that shoulder back...If for any reason I feel a little extra resistance, I'll pull back and do the shoulder in two steps just like I did with the neck. After the first one I measured and lowered my die just a few thou and finally got it to where the 375 Ruger was sized down and coming out within 0.0005....aka half a thou of my ADG brass measured from base to shoulder using a Short Action Customs 30 degree shoulder angle Comparator Gauge. They came out pretty nice.

375_6.png


375 Ruger on the left and 300 PRC on the right. The surprising part is: After all this, I measured the OAL and came to 3.871 on all of them. I trim at 3.870 and my trimmer barely made a sound as I took these to 3.870. I ran them through a neck expander mandrel that slightly moved them out to what I prefer my neck tension to be. I will load these up and probably shoot them this weekend. I'll anneal them after and run them through the reloading process just like the ADG brass and see if some of that brass flows forward and grows. I will see just how much brass I have to trim. I'm expecting a little flow forward. We will see. If I do see a donut forming I will neck ream and report my findings.

These should shoot just wonderful. The only problem they should have is the inherent primer pocket failures that are known in Hornady brass. I hope this tutorial will help at least one person who may be stuck in a situation where they want to shoot their 300PRC but either have no brass, or they are afraid of damaging/losing the precious little they have.
 
Just in case someone gets froggy and tries to do this in one step....in one pull of the press handle...here is what happens when you try to go too fast:


You get some nice dents that should go away when fire formed....however, you never know if they will create a crease and crack the brass. So, just go slow and take your time.
 

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So, we all know that ammo for the 300PRC is scare in the market place. We also know that finding reloading components have been frustratingly scarce as well. Powders hit websites and are sold out in mere seconds. Same with primers, bullets and brass. With ADG not planning to come to market with more 300PRC brass until months from now, and the Lapua release that may get back up into summer, what exactly are we to do? Buy Hornady brass? Have you tried finding that lately? It has been gobbled up off the market as well. With competition season approaching, many people are getting nervous about not having anything. I myself have lowered my powder loads on my 230gr A-Tips and my new 245gr EOL's just to baby my brass so it will last longer.

Well, let me give you an alternative. Just incase the brass of ADG and Lapua get pushed back to a point that makes it to where you can't shoot, let's walk through one of the simplest brass resizing/substitution jobs you will ever encounter. I'll walk through how to turn 375 Ruger brass into 300 PRC. Yes, going from the parent to the child case. After this you will see how simple it is, and you will see that it wasn't much innovation to take the 375 Ruger to the 300 PRC. Wildcatters did it first and Hornady just SAAMI spec'd it and called it Easy Money. The cartridge is my current favorite for 1000 to 2000 yards...and slightly beyond. Now...let's take a look.

So, I'm using my normal full length sizing die with the expander ball removed...I never run an expander ball. I'm using a 334 bushing. I would not use a non-bushing die because it squeezes down too small. I did not find it necessary to go bigger and do two or more sizing operations making the neck smaller each time. I did however only partially size in a few steps pushing the neck in and the shoulder back. Let's take a look:

View attachment 7532157

The 375 Ruger next to the 300PRC. You will notice that the cases are really close in OAL. You will notice that the 375 neck is much higher up and the shoulder angle is different. Everything else is very close, like body taper. So, I sprayed everything with Hornady One Shot and let dry. Next I attacked only half of the neck.

View attachment 7532159

You will notice I only did a partial neck sizing. Look how the brass being squeezed in for the new neck diameter and flowing down. I only did a partial size here, lifted the handle...and then gently went for the remainder of just the neck.

View attachment 7532163

Neck is done, but we haven't attacked that shoulder yet. What I do here is to slowly push that shoulder back...If for any reason I feel a little extra resistance, I'll pull back and do the shoulder in two steps just like I did with the neck. After the first one I measured and lowered my die just a few thou and finally got it to where the 375 Ruger was sized down and coming out within 0.0005....aka half a thou of my ADG brass measured from base to shoulder using a Short Action Customs 30 degree shoulder angle Comparator Gauge. They came out pretty nice.

View attachment 7532165

375 Ruger on the left and 300 PRC on the right. The surprising part is: After all this, I measured the OAL and came to 3.871 on all of them. I trim at 3.870 and my trimmer barely made a sound as I took these to 3.870. I ran them through a neck expander mandrel that slightly moved them out to what I prefer my neck tension to be. I will load these up and probably shoot them this weekend. I'll anneal them after and run them through the reloading process just like the ADG brass and see if some of that brass flows forward and grows. I will see just how much brass I have to trim. I'm expecting a little flow forward. We will see. If I do see a donut forming I will neck ream and report my findings.

These should shoot just wonderful. The only problem they should have is the inherent primer pocket failures that are known in Hornady brass. I hope this tutorial will help at least one person who may be stuck in a situation where they want to shoot their 300PRC but either have no brass, or they are afraid of damaging/losing the precious little they have.
Thanks.

That is the one case I have been able to find locally. I will have to pick some up and work it up.
 
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Any concern on a donut forming inside? Have you checked with a plug guage?

I didn't see anything when I did them....and then I ran a mandrel thru them....so anything inside would have pushed outside. Once I fire them I will check. I do expect some brass to flow forward...I'll check with pin gauges when I reload.
 
Some recent load testing in the AXMC with 27" barrel. N565 and RL26 with the Hornady 225 ELDM. Virgin Hornady brass and F210M. 40 degrees and a DA of 200.

The N565 load was much hotter than I expected. Heavy bolt lift at 79.6 and up. I'll probably re-run the test in the 76gr area.

N565___H225-1787103.jpg


RL26_H225-1787110.jpg
 

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B2lee, do you have to turn the necks on the necked down 375 Ruger brass? Also what do you use to ream the necks if a donut does form?

No neck turn...just a simple neck down.....if a donut shows up...I'll use a LE Wilson trimmer with the neck reamer attachment.

However....I'm looking for an excuse for an IDOD :)... the new version is only like $2500.
 
Try finding some... :(

I saw plenty earlier today....but they had bullets and powder already in them....and too expensive. However, I've recently seen some Nosler 375 Ruger brass in stock...and I was going to pick them up...but decided not to.
 
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Some recent load testing in the AXMC with 27" barrel. N565 and RL26 with the Hornady 225 ELDM. Virgin Hornady brass and F210M. 40 degrees and a DA of 200.

The N565 load was much hotter than I expected. Heavy bolt lift at 79.6 and up. I'll probably re-run the test in the 76gr area.

N565___H225-1787103.jpg


RL26_H225-1787110.jpg
HI,
I was trying similar loads with 230 A-Tip and no bold stickiness at all but I BACKED OFF after checking pressures with GRT, this load is flaged as dangerous overpressure. I will wait until Nammo publishes N565 load data. There is some people using N565 around the forum but we all are in danger of serious over-pressure until official data is published. Here you have the output of GRT about your load.
 

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So, we all know that ammo for the 300PRC is scare in the market place. We also know that finding reloading components have been frustratingly scarce as well. Powders hit websites and are sold out in mere seconds. Same with primers, bullets and brass. With ADG not planning to come to market with more 300PRC brass until months from now, and the Lapua release that may get back up into summer, what exactly are we to do? Buy Hornady brass? Have you tried finding that lately? It has been gobbled up off the market as well. With competition season approaching, many people are getting nervous about not having anything. I myself have lowered my powder loads on my 230gr A-Tips and my new 245gr EOL's just to baby my brass so it will last longer.

Well, let me give you an alternative. Just incase the brass of ADG and Lapua get pushed back to a point that makes it to where you can't shoot, let's walk through one of the simplest brass resizing/substitution jobs you will ever encounter. I'll walk through how to turn 375 Ruger brass into 300 PRC. Yes, going from the parent to the child case. After this you will see how simple it is, and you will see that it wasn't much innovation to take the 375 Ruger to the 300 PRC. Wildcatters did it first and Hornady just SAAMI spec'd it and called it Easy Money. The cartridge is my current favorite for 1000 to 2000 yards...and slightly beyond. Now...let's take a look.

So, I'm using my normal full length sizing die with the expander ball removed...I never run an expander ball. I'm using a 334 bushing. I would not use a non-bushing die because it squeezes down too small. I did not find it necessary to go bigger and do two or more sizing operations making the neck smaller each time. I did however only partially size in a few steps pushing the neck in and the shoulder back. Let's take a look:

View attachment 7532157

The 375 Ruger next to the 300PRC. You will notice that the cases are really close in OAL. You will notice that the 375 neck is much higher up and the shoulder angle is different. Everything else is very close, like body taper. So, I sprayed everything with Hornady One Shot and let dry. Next I attacked only half of the neck.

View attachment 7532159

You will notice I only did a partial neck sizing. Look how the brass being squeezed in for the new neck diameter and flowing down. I only did a partial size here, lifted the handle...and then gently went for the remainder of just the neck.

View attachment 7532163

Neck is done, but we haven't attacked that shoulder yet. What I do here is to slowly push that shoulder back...If for any reason I feel a little extra resistance, I'll pull back and do the shoulder in two steps just like I did with the neck. After the first one I measured and lowered my die just a few thou and finally got it to where the 375 Ruger was sized down and coming out within 0.0005....aka half a thou of my ADG brass measured from base to shoulder using a Short Action Customs 30 degree shoulder angle Comparator Gauge. They came out pretty nice.

View attachment 7532165

375 Ruger on the left and 300 PRC on the right. The surprising part is: After all this, I measured the OAL and came to 3.871 on all of them. I trim at 3.870 and my trimmer barely made a sound as I took these to 3.870. I ran them through a neck expander mandrel that slightly moved them out to what I prefer my neck tension to be. I will load these up and probably shoot them this weekend. I'll anneal them after and run them through the reloading process just like the ADG brass and see if some of that brass flows forward and grows. I will see just how much brass I have to trim. I'm expecting a little flow forward. We will see. If I do see a donut forming I will neck ream and report my findings.

These should shoot just wonderful. The only problem they should have is the inherent primer pocket failures that are known in Hornady brass. I hope this tutorial will help at least one person who may be stuck in a situation where they want to shoot their 300PRC but either have no brass, or they are afraid of damaging/losing the precious little they have.
I picked up some 375 Ruger brass and sized it down. My first attempt failed and I wound up removing the bushing from my die to do the initial sizing. I reinstalled the bushing and ran them through again to finish sizing the neck and to bump the shoulder back to match my Hornady 300PRC brass. I also ran them through my mandrel die to expand the necks.

300PRC brass (left) 375 Ruger brass sized down (right)
20210121_174833.jpg

I had a few at first where I had to much lube on the shoulder. They have dents from the Hydraulic pressure. Overall im happy with the results. The case overall length is right in line with b2lee's result of 2.871" When I get my barrel chambered I will give them a shot.
20210122_192535.jpg

Side by side with little difference in appearance.
20210122_192529.jpg

Here is one that I over lubricated.
20210122_192455.jpg

Oops..
20210122_194255.jpg
 
@JBarton very good. I'll be at the range tomorrow at around 1pm ET....shooting my 375 Ruger brass. I'll be looking for brass growth....but I'll also measure speeds and groups. I did just spin on my old barrel with like 1338 rounds on it...I'm not going to go test with my new barrel. They were made with the same reamer/smith and the fired brass from one to the other are within half a thou...

I'm pretty sure the groups will suck...because the barrels are different lengths....the new one has a different brake and the ATS tuner. The old barrel...I'm just going to run it with a Lil'B brake and no tuner....and loads are CIP length....so if it shoots a 1/2" group it will be more luck of picking a seating depth than anything. I'll be shooting 49 rounds tomorrow. I saved 1 piece of brass as a show piece...a conversation piece with people at the range.

I'll post something tomorrow night.
 
@JBarton very good. I'll be at the range tomorrow at around 1pm ET....shooting my 375 Ruger brass. I'll be looking for brass growth....but I'll also measure speeds and groups. I did just spin on my old barrel with like 1338 rounds on it...I'm not going to go test with my new barrel. They were made with the same reamer/smith and the fired brass from one to the other are within half a thou...

I'm pretty sure the groups will suck...because the barrels are different lengths....the new one has a different brake and the ATS tuner. The old barrel...I'm just going to run it with a Lil'B brake and no tuner....and loads are CIP length....so if it shoots a 1/2" group it will be more luck of picking a seating depth than anything. I'll be shooting 49 rounds tomorrow. I saved 1 piece of brass as a show piece...a conversation piece with people at the range.

I'll post something tomorrow night.
Looking forward to seeing your results.
 
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Here is the update to Tuesdays post on converting 375 Ruger brass to our beloved 300PRC. Let me throw some caveats out first. Today was a sunny day but cold to me. High while I was at the range was 30F. Very light wind. Elevation 931ft ASL. Humidity 54%....blah blah...like that matters. It was a sunny and cold day. Range shot is 100 yards.

Now...to something that does matter. Brass is virgin brass that was necked down to 300 PRC using my normal full length sizing die with a 334 bushing. No expander button. The brass was NOT annealed before or after doing any of these steps. Primer is a Fed #215M. Powder/charge is 75.0 grains of RL-26 measured to the kernel with an Autotrickler V3. Bullet used is the 245gr Berger EOL. Seating depth is an arbitrary seating depth. It fits in the CIP mags. No work up of any kind for seating depth...and all rounds were shot prepared exactly the same.

Barrel used: I spun off my new barrel and put back on my old barrel...that now has about 1400 rounds through it. It is a Bartlein with 1-9 twist at 28 inches. No ATS tuner. Muzzle brake used is the old Lil'B that I ran last year. Bipod used was the Pheonix and a Precision Undergroung ELR rear bag was used. Now that all the bullshit disclaimers are out of the way....let's actually see pictures and data.

Group #1

group1.png


You will see my first shot really low and almost off paper. This is mainly due to having a freshly cleaned barrel and their may have been just a bit of Boretech cleaner coating the barrel. Some of it is due to going from a 29.5" to a 28.0 inch barrel....and shooting at 30F instead of like 58F the last time I shot. So I over compensated and dialed up and right and the second shot is high right. I dialed down and over and the 3 shots make up a small group. So...this was the first group and sets up the test with a nice-ish zero and a fouled barrel. The speeds for this group were:

2812
2824
2845
2856
2839

The first two are understandable but more than I'd like on the others....but this is virgin brass that has been necked down and the seating tension from round to round was extremely different....just going by feel in a K&M Arbor Press.

Next...Group #2

group2.png


I didn't call any fliers here. Everything felt good and normal. This group just is what it is. Speeds for this group are as follows:

2827
2838
2830
2837
2814

Well outside my acceptable ES...but again...it is what it is with this new converted brass.

Next.....Group #3

group3.png


There is a caveat with this group. All trigger presses felt good...but 4 out of 5 of these were the dented necks that I showed an example of. I segregated all of them into this group so the rest of the groups would not have an excuse. Speeds are as follows.

2829
2829
2847
2843
2834

Seems to be the standard pattern with ES on this.

Now...on to Group #4

group4.png


Yep, cherry picking time. At 1400 rounds I can still say this is a 1/2MOA rifle. Probably just screwed up 5 different trigger pulls with 5 different ways. Looks good on paper but probably more luck considering the ammo and barrel used. Looks promising but the ES's were too high for my liking....Speeds were:

2812
2838
2830
2838
2826

Next....Group #5

group5.png


Nothing special...just a typical group with ES's that I'm not happy with. Speeds are:

2826
2824
2857
2849
2858

Next up....Group #6

group6.png


I don't feel I pulled that shot to the right. I just think it is a flier of a non-dialed group. Trigger pulls felt really good. Speeds for this group are.

2822
2842
2860
2848
2829

I decided here to take the MagnetoSPeedV3 off. It is not attached to the barrel and uses the MK Machine mount. I thought maybe I could squeeze a better group without it mounted....eventhough it doesn't really make a difference. No more speed data.

Next up....Group #7

group7.png


Not bad....trigger pulls felt nice. Not horrible...especially given the circumstances.

Next up....Group #8

group8.png


Ok...here is the one time I'll say I did something wrong...something majorly wrong. I had a sympathetic squeeze on the rear bag while my trigger finger was squeezing. I cussed myself for a few seconds. You can't afford to have stupid mistakes like that when you are shooting ELR. Probably would have been in the dirt in front of the target at 2000yds. Other than that....a surprisingly good group under the conditions.

So, after cussing myself...I noticed that my allotted time was almost over and I had 9 more rounds to shoot....started with 49. I sent the next 9 into a big diamond target very...very quickly to fire form the brass. So quickly it was a 9 shot group that would have been 2.5 inches in size. I wasn't really concerned about accuracy...just getting it done and getting my stuff packed before the next reservation was there to shoot.

Here is a look at the fired primers:

fired_brass_375.png


Things look great. Going to clean some things up and I'll be in the shop running this brass through my normal reloading process including annealing. I will take some measurements and see just how much the brass moved, grew in length....check for donuts...and what the seating neck tension is on the next go around.

I hope you guys can appreciate my findings today. I hope it atleast helps a few people out who can't find 300PRC brass but can buy 375 Ruger brass that is gathering dust on local shelves. I hope to see you guys on the big boy range soon.
 
Grafs will let you place a backorder on N565, N570, H1000, RL26 etc. at the minute. Same goes for Lapua 300 PRC brass. No such luck on primers.

I am thinking about just putting in big backorder as I hope to start reloading for 300 PRC later this year. Is there any consensus on which powder is best? Temperature stability and consistency are more important to me than max muzzle velocity. I will have a 26" barrel. Aiming to use mostly 200-230 grain bullets.
 
Some recent load testing in the AXMC with 27" barrel. N565 and RL26 with the Hornady 225 ELDM. Virgin Hornady brass and F210M. 40 degrees and a DA of 200.

The N565 load was much hotter than I expected. Heavy bolt lift at 79.6 and up. I'll probably re-run the test in the 76gr area.

N565___H225-1787103.jpg


RL26_H225-1787110.jpg
You are using large rifle instead of magnum primers and it is working out for you? Very nice, do you still start the load 10% under when you are switching primers? I am still kind of new to reloading....
 
So, since the last post about the 375 Ruger to 300 PRC conversion on some Hornady brass, I've deprimed, wet tumbled, dried, annealed, full length sized with 334 neck bushing while only bumping back the shoulder 2 thou, neck mandreled, trimmed, chamfered and deburred everything. I also gauged the primer pockets and everything is good there.

I measured the base of the web and the thickness was 0.5325 and after sizing 0.5320...so a half thou base sized back to SAAMI spec. Neck thickness is 15thou. Upon trimming....probably 80% didn't even kiss the cutter....while a few cut a half thou off...and only 3 cut about a full thou off. So growth was none to minimal.

The big thing was....this time around....everything felt the same. Using a Rock Chucker IV with a ball handle instead of the roller handle...I get a good feel for any changes....unlike some of my other set ups where things are set up for my comfort and speed. Full length sizing was much easier than expected. Probably had to do with a good anneal and only bumping back 2 thou. Neck Mandrel opened up the mouths very easily with very little resistance and minimal spring back.

All in all...everything felt very consistent and I felt I was doing the minimal to the brass to achieve my goal. I'll load some up soon and give feedback on how easy the bullets seated. Maybe next week...if the weather would break...I'll go back to the range and shoot some across the chronograph. I expect to see those Extreme Spreads drop down to something I'd be happy with...along with a nice tight SD. Not really expecting much out of the groups, since I'll once again use the old barrel to do the testing work.

There is one negative. The picture I showed of a few divots in the neck...after fire forming and the rest of the process....it appears in the future it will split the neck. Next time...if there is a next time...I will anneal before the entire process. DO NOT ANNEAL FIRST {It will crush the necks too easily instead of forming them} I didn't anneal this time because I feel annealing is something a lot of new reloaders can't/won't do. The tutorial was to show how anyone can do it. But annealing before starting...is the way to go. Pictured below is a future split neck.

opps2.png
 
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I have noticed, uncharacteristically, that all my Hornady 6.5PRC brass has a tendency to split in either the shoulder of the neck upon resizing after the initial firing. I have to anneal it after every firing and push it to the limit of what I like to see in color change in the flame to keep this cracking from happening. Maybe it will be the same scenario with their 375 Ruger brass too.
I haven't started my 300PRC build and trying to decide on an action. Kauger Arms makes what he calls a 300PRC action but, with his floating bolt head, I could use the 338LM action with a standard magnum bolt head. That would give me the ability to also set up a 338LM for the same action.
I have ADG brass, a 9 twist Krieger HV and Whidden dies here and ready, along with Berger 230 OTM Hybrids and 215 Hybrids.