Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn.
- Thread starter glock63
- Start date
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1shot2kill</div><div class="ubbcode-body">1 in 10 </div></div>
+1
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1shot2kill</div><div class="ubbcode-body">1 in 10 </div></div>
+1
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patches</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1shot2kill</div><div class="ubbcode-body">1 in 10 </div></div>
+1 </div></div>
.........and another vote for 1:10
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patches</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1shot2kill</div><div class="ubbcode-body">1 in 10 </div></div>
+1 </div></div>
.........and another vote for 1:10
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patches</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1shot2kill</div><div class="ubbcode-body">1 in 10 </div></div>
+1 </div></div>
.........and another vote for 1:10 </div></div>
My AIAW, which is a 1:12" twist stabilizes very thing up to the 208 AMAX just fine out to 1000 yards and then some.....
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patches</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1shot2kill</div><div class="ubbcode-body">1 in 10 </div></div>
+1 </div></div>
.........and another vote for 1:10 </div></div>
My AIAW, which is a 1:12" twist stabilizes very thing up to the 208 AMAX just fine out to 1000 yards and then some.....
Re: .308 twist rate?
with a 1 in 12 you are limited to a lower weight the slower twist wont stabilize heavy longer bullets ie 190-208 and in my expierience the 1 in 11.25 does one weight very well and the others not so much but the 1 in 10 does all pretty well but that is my .02
however what i recomend for people who are asking what barrel should i get or what twist rate is to figure out what kind of shooting you will be doing so lets say f class 1000 yard what i do is see who is winning competitions and what they are using so if joe blow and his nearest compeditors are using shillen and bartlien barrels it is pretty safe to say that they are a good way to go and if they are using 1 in 14 or 1 in 12 then go that route.
for the longest time i believed that i had to have flutes in my barrels or they werent worth a dawm then one day someone stated to me how many competitive shooters do you see with fluted barrels and after a lot of searching i couldnt find any so to sumarize figure out what you want to do with it then find what catagory it falls into and then use what the winners use
with a 1 in 12 you are limited to a lower weight the slower twist wont stabilize heavy longer bullets ie 190-208 and in my expierience the 1 in 11.25 does one weight very well and the others not so much but the 1 in 10 does all pretty well but that is my .02
however what i recomend for people who are asking what barrel should i get or what twist rate is to figure out what kind of shooting you will be doing so lets say f class 1000 yard what i do is see who is winning competitions and what they are using so if joe blow and his nearest compeditors are using shillen and bartlien barrels it is pretty safe to say that they are a good way to go and if they are using 1 in 14 or 1 in 12 then go that route.
for the longest time i believed that i had to have flutes in my barrels or they werent worth a dawm then one day someone stated to me how many competitive shooters do you see with fluted barrels and after a lot of searching i couldnt find any so to sumarize figure out what you want to do with it then find what catagory it falls into and then use what the winners use
Re: .308 twist rate?
I dont compete, just enjoy shooting and am just getting into the long range thing. Id like to shoot bullets from 175 and up, hopefully out to 1k eventually. Im gonna try out a T rifled barrel from bartlein. Just trying to decide on the twist. Also, subsonics may be in the equation as I am waiting on ATF approval for an AAC cyclone suppressor.
I dont compete, just enjoy shooting and am just getting into the long range thing. Id like to shoot bullets from 175 and up, hopefully out to 1k eventually. Im gonna try out a T rifled barrel from bartlein. Just trying to decide on the twist. Also, subsonics may be in the equation as I am waiting on ATF approval for an AAC cyclone suppressor.
Re: .308 twist rate?
I went with a 1:11 twist Bartlein 5R. My smith put it chambered it for 175gr SMKs, so I don't think I'd be able to take full advantage of the 208s or other longer pills. It shoots the 175s great though. Very happy with it. If you went with a tighter twist, you may have trouble with the lighter pills.
I went with a 1:11 twist Bartlein 5R. My smith put it chambered it for 175gr SMKs, so I don't think I'd be able to take full advantage of the 208s or other longer pills. It shoots the 175s great though. Very happy with it. If you went with a tighter twist, you may have trouble with the lighter pills.
Re: .308 twist rate?
The 1:11.25 is fine for up to 200gr SMK or even longer. I have shot that bullet to 1000 yards with that twist. No issues.
I know nothing of subsonics or suppressor use; I'm just a dumb F-class LR shooter and I have a 1:11.25 twisted barrel.
The 1:11.25 is fine for up to 200gr SMK or even longer. I have shot that bullet to 1000 yards with that twist. No issues.
I know nothing of subsonics or suppressor use; I'm just a dumb F-class LR shooter and I have a 1:11.25 twisted barrel.
Re: .308 twist rate?
For the most part a 1-12 will handle up to conventional match type bullets up to 190gr. at .308 win. velocities.
The 200's you have to go to at least a 1-11 if not faster. It depends on the bullet, velocity etc.....
The 208's From Hornady for example at 3000fps. according to my twist calcs. need something like a 10.78 min. The barrels we make the guys at Hornady are all 1-10 for they're bench guns. We did make one of they guys there a 1-11 and he said it was good and could win a match with it but the 1-10 twist barrels seemed to be working better.
Berger lists a 1-11 for the 210Vld's and I do know it works but am more comfortable with a slightly faster twist. One F-Class gun we put barrels on for a guy and it is chambered in .300win mag. and he is pushing the 210's at 2950fps. I've shot the gun myself at 200 yards and the gun is a 1/4 min. gun. I've competed against the guy at matches and have seen the gun shoot at a 1000 yards and it's a hammer. The barrels we make him are 1-10.
A faster twist barrel does not hurt you like most people think it does. The key is good ammo with good bullets plays a part. The more runout your ammo has or the poorer quality bullet a faster twist will have more of an adverse effect on the accuracy.
Just a few months ago I rebuilt my 1903 Springfield as a Model 1941 USMC sniper rifle with a Unertl scope. 1-11 twist barrel and the main bullet I shoot is the 155gr. Lapua's. It's a 1/3 moa gun if I pull the trigger right.
Later, Frank
Bartlein Barrels
For the most part a 1-12 will handle up to conventional match type bullets up to 190gr. at .308 win. velocities.
The 200's you have to go to at least a 1-11 if not faster. It depends on the bullet, velocity etc.....
The 208's From Hornady for example at 3000fps. according to my twist calcs. need something like a 10.78 min. The barrels we make the guys at Hornady are all 1-10 for they're bench guns. We did make one of they guys there a 1-11 and he said it was good and could win a match with it but the 1-10 twist barrels seemed to be working better.
Berger lists a 1-11 for the 210Vld's and I do know it works but am more comfortable with a slightly faster twist. One F-Class gun we put barrels on for a guy and it is chambered in .300win mag. and he is pushing the 210's at 2950fps. I've shot the gun myself at 200 yards and the gun is a 1/4 min. gun. I've competed against the guy at matches and have seen the gun shoot at a 1000 yards and it's a hammer. The barrels we make him are 1-10.
A faster twist barrel does not hurt you like most people think it does. The key is good ammo with good bullets plays a part. The more runout your ammo has or the poorer quality bullet a faster twist will have more of an adverse effect on the accuracy.
Just a few months ago I rebuilt my 1903 Springfield as a Model 1941 USMC sniper rifle with a Unertl scope. 1-11 twist barrel and the main bullet I shoot is the 155gr. Lapua's. It's a 1/3 moa gun if I pull the trigger right.
Later, Frank
Bartlein Barrels
Re: .308 twist rate?
Terry Cross put an Obermeyer 5R in 11.25 twist on the M40A1 he built for me back in 2000. I've shot 155 Scenar's, 175 SMK's, and 190 SMK's through it, all with fine accuracy but have settled on an M118LR clone (175 SMK) as my go-to for this rifle. I'll reserve the heavier bullets for my .300WM, which has a 1/10 twist and loves the 210 Berger.
A famous barrel maker once remarked that the 11.25/1 twist is the answer for the .308 shooter who can't make up his mind between a 1/10 and a 1/12
Terry Cross put an Obermeyer 5R in 11.25 twist on the M40A1 he built for me back in 2000. I've shot 155 Scenar's, 175 SMK's, and 190 SMK's through it, all with fine accuracy but have settled on an M118LR clone (175 SMK) as my go-to for this rifle. I'll reserve the heavier bullets for my .300WM, which has a 1/10 twist and loves the 210 Berger.
A famous barrel maker once remarked that the 11.25/1 twist is the answer for the .308 shooter who can't make up his mind between a 1/10 and a 1/12
Re: .308 twist rate?
For 30 cal barrels I always order 12 twist for use up to 190 gr.
13 to 13.5 twist for up to 168s. I havea 5R 13.8 that loves 168s
14 twist up to 155 gr. I have a 14 twist that eats 168s nicely as well.
For 30 cal barrels I always order 12 twist for use up to 190 gr.
13 to 13.5 twist for up to 168s. I havea 5R 13.8 that loves 168s
14 twist up to 155 gr. I have a 14 twist that eats 168s nicely as well.
Re: .308 twist rate?
I shoot 175's out of a 1 in 12 with good accuracy consistently, so a 1 in 11.25 or 11 should hold a 190 pretty stable.
I shoot 175's out of a 1 in 12 with good accuracy consistently, so a 1 in 11.25 or 11 should hold a 190 pretty stable.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: prplhaz72</div><div class="ubbcode-body">Well I think the way to solve this is get one that starts as 1-11" and ends at 1-10"
</div></div>
Actually if I had $$$ laying around, I'd seriously be looking at getting a gain twist barrel.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: prplhaz72</div><div class="ubbcode-body">Well I think the way to solve this is get one that starts as 1-11" and ends at 1-10"
Actually if I had $$$ laying around, I'd seriously be looking at getting a gain twist barrel.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: prplhaz72</div><div class="ubbcode-body">Well I think the way to solve this is get one that starts as 1-11" and ends at 1-10"
</div></div>
Actually if I had $$$ laying around, I'd seriously be looking at getting a gain twist barrel. </div></div>
Thats what Im ordering. 11.5 to 11.25, finished at 22 inches.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sobrbiker883</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: prplhaz72</div><div class="ubbcode-body">Well I think the way to solve this is get one that starts as 1-11" and ends at 1-10"
Actually if I had $$$ laying around, I'd seriously be looking at getting a gain twist barrel. </div></div>
Thats what Im ordering. 11.5 to 11.25, finished at 22 inches.
Re: .308 twist rate?
1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
G
Guest
Guest
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
One word,...Marketing,...and nothing more.
The buying public, believes everything they see or read as fact.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
One word,...Marketing,...and nothing more.
The buying public, believes everything they see or read as fact.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn. </div></div>
Barrel length ? If barrel shorter than 20" i'd go with 1-10 and .299 bore diameter ...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn. </div></div>
Barrel length ? If barrel shorter than 20" i'd go with 1-10 and .299 bore diameter ...
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: D ICE 308</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn. </div></div>
Barrel length ? If barrel shorter than 20" i'd go with 1-10 and .299 bore diameter ...</div></div>
Why is this ? Get good stabilization on the pill in the shorter tube that you may not get if you went with say 1 in 12" with a short barrel ?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: D ICE 308</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn. </div></div>
Barrel length ? If barrel shorter than 20" i'd go with 1-10 and .299 bore diameter ...</div></div>
Why is this ? Get good stabilization on the pill in the shorter tube that you may not get if you went with say 1 in 12" with a short barrel ?
Re: .308 twist rate?
Ya think? I looked for the facetious / eye-rolling emoticon, but I just couldn't find it.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gunfighter14e2</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
One word,...Marketing,...and nothing more.
The buying public, believes everything they see or read as fact.
</div></div>
Ya think? I looked for the facetious / eye-rolling emoticon, but I just couldn't find it.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gunfighter14e2</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
One word,...Marketing,...and nothing more.
The buying public, believes everything they see or read as fact.
</div></div>
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Blue-Printed_LFE</div><div class="ubbcode-body">1:10 handles mostly everything</div></div>
Anyone else notice the resurrection??
One year later, I would have to say 1:10, again.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Blue-Printed_LFE</div><div class="ubbcode-body">1:10 handles mostly everything</div></div>
Anyone else notice the resurrection??
One year later, I would have to say 1:10, again.
Re: .308 twist rate?
I believe the higher the altitude the slower the twist rate can be. I am at 1000ft over Sea level and 195's shoot fine out of my GAP 308. (5R 11.25)--Brandon
I believe the higher the altitude the slower the twist rate can be. I am at 1000ft over Sea level and 195's shoot fine out of my GAP 308. (5R 11.25)--Brandon
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: D ICE 308</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn. </div></div>
Barrel length ? If barrel shorter than 20" i'd go with 1-10 and .299 bore diameter ... </div></div>
Don't understand the logic behind shorter barrel faster twist? Does barrel length dictate twist? As long as the bullet is stable I would think one would want a slower twist especially in a shorter barrel since the MV is already slower? Why slow it down even more w/ a faster twist?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: D ICE 308</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glock63</div><div class="ubbcode-body">Im ordering a barrel from Bartlein and trying to decide if I should go with a faster twist than 11.25. Id like to shoot bullets from 175 to 190 grn. </div></div>
Barrel length ? If barrel shorter than 20" i'd go with 1-10 and .299 bore diameter ... </div></div>
Don't understand the logic behind shorter barrel faster twist? Does barrel length dictate twist? As long as the bullet is stable I would think one would want a slower twist especially in a shorter barrel since the MV is already slower? Why slow it down even more w/ a faster twist?
Re: .308 twist rate?
I'm not up on the short barrel thing, only thing I can think is that you would be sacrificing stability with a shorter barrel if you don't get enough twist before the bullet reaches the end of the barrel. Since you give up distance of twist inside the barrel, you would be making up for it with the faster twist. Not sure if that's true, just what I thought in my head haha
I'm not up on the short barrel thing, only thing I can think is that you would be sacrificing stability with a shorter barrel if you don't get enough twist before the bullet reaches the end of the barrel. Since you give up distance of twist inside the barrel, you would be making up for it with the faster twist. Not sure if that's true, just what I thought in my head haha
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Snipedogg</div><div class="ubbcode-body">I'm not up on the short barrel thing, only thing I can think is that you would be sacrificing stability with a shorter barrel if you don't get enough twist before the bullet reaches the end of the barrel. Since you give up distance of twist inside the barrel, you would be making up for it with the faster twist. Not sure if that's true, just what I thought in my head haha </div></div>
New here, and I've been curious about this myself. I was under the impression (may be wrong) that once you reached a certain threshold in length, the additional length of the barrel did not effect the stability of the bullet. (MV is of course effect by barrel length) Can anyone clear this up?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Snipedogg</div><div class="ubbcode-body">I'm not up on the short barrel thing, only thing I can think is that you would be sacrificing stability with a shorter barrel if you don't get enough twist before the bullet reaches the end of the barrel. Since you give up distance of twist inside the barrel, you would be making up for it with the faster twist. Not sure if that's true, just what I thought in my head haha </div></div>
New here, and I've been curious about this myself. I was under the impression (may be wrong) that once you reached a certain threshold in length, the additional length of the barrel did not effect the stability of the bullet. (MV is of course effect by barrel length) Can anyone clear this up?
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
That f**king word 'TACTICAL' again. You can buy tactical knifes, pens, notebooks, walking sticks, coffee cups, thermal vests, keyrings just about everything. New marketing ploy seems to be write TACTICAL on a new or existing product and a whole bunch of idiots with more money than sense will whale up and buy it. A barrel is a barrel no matter what is written on it.
Oh and go 1 in 11.25, seems to shoot nearly everything well.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
That f**king word 'TACTICAL' again. You can buy tactical knifes, pens, notebooks, walking sticks, coffee cups, thermal vests, keyrings just about everything. New marketing ploy seems to be write TACTICAL on a new or existing product and a whole bunch of idiots with more money than sense will whale up and buy it. A barrel is a barrel no matter what is written on it.
Oh and go 1 in 11.25, seems to shoot nearly everything well.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fuscalino</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
That f**king word 'TACTICAL' again. </div></div>
I dont care if it has "Pink Unicorn" stamped on the side... Its the only 700 in .308 that comes with a 1-10" twist. And for less than $$600... already threaded... If your looking to fire the heavies out of a 308 you cant beat that... I am curious though.. How much cheaper it would be if "Tactical" wasnt stamped on the barrel...
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fuscalino</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: patsim</div><div class="ubbcode-body">1:10 if you're going to be doing any tactical shooting.
That's the ratio for the Rem 700-AAC--and it says "TACTICAL RIFILING" right on the barrel. Seriously.
</div></div>
That f**king word 'TACTICAL' again. </div></div>
I dont care if it has "Pink Unicorn" stamped on the side... Its the only 700 in .308 that comes with a 1-10" twist. And for less than $$600... already threaded... If your looking to fire the heavies out of a 308 you cant beat that... I am curious though.. How much cheaper it would be if "Tactical" wasnt stamped on the barrel...
Re: .308 twist rate?
A 1-12 twist at .308 velocities will handle up to conventional 190gr. match bullets. Some of the solid type bullets being longer in length might need a faster twist etc...
If you are shooting good quality bullets you won't see any difference in accuracy between a 1-10, 11, 11.25, 12 twist barrel etc....A faster twist barrel with poor quality ammo or bullets can effect accuracy.
Later, Frank
Bartlein Barrels
A 1-12 twist at .308 velocities will handle up to conventional 190gr. match bullets. Some of the solid type bullets being longer in length might need a faster twist etc...
If you are shooting good quality bullets you won't see any difference in accuracy between a 1-10, 11, 11.25, 12 twist barrel etc....A faster twist barrel with poor quality ammo or bullets can effect accuracy.
Later, Frank
Bartlein Barrels
Re: .308 twist rate?
1:11.25
Ive shot 155s to 190s and gone sub-half moa with all of it. just my 2 cents.
1:11.25
Ive shot 155s to 190s and gone sub-half moa with all of it. just my 2 cents.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Snipedogg</div><div class="ubbcode-body">I'm not up on the short barrel thing, only thing I can think is that you would be sacrificing stability with a shorter barrel if you don't get enough twist before the bullet reaches the end of the barrel. Since you give up distance of twist inside the barrel, you would be making up for it with the faster twist. Not sure if that's true, just what I thought in my head haha</div></div>
The only thing that would affect stability in relation to barrel length is if the barrel was so short(or long) that the velocity was substantially different. That inch or two is only going to change the velocity and thus the spin rate of the bullet by a very small amount. The stability of the bullet is based pretty much on its length and how fast its turning. There are online calculators out there that can tell you how fast you need to spin a certain bullet to keep it within theoretical norms.
Spinning the bullet faster than necessary doesn't really hurt accuracy unless you are shooting well beyond the range of most rifles or are using subpar components. Variations in jacket thickness can cause unbalance which will cause wobble, jackets too thin might fail, bullets not square and concentric will lose accuracy. Overstabilizing the bullet is more a problem with long range artillery than with rifles......
going with the 1-10 twist will give you more versatility if you can seat the light bullets out far enough to keep the bullet close to the lands. Some mags won't allow that so its one thing to think about in your decision. Being able to shoot the long heavies is nice sometimes but might not really gain you that much either unless you can get the velocity that makes it worthwhile. 220's in a .308 don't really make much sense but 190's are great.....1-10 or 1-11.25 should be fine for everything up to that in standard .308 bullets.
You must choose as you have to live with it...
Frank
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Snipedogg</div><div class="ubbcode-body">I'm not up on the short barrel thing, only thing I can think is that you would be sacrificing stability with a shorter barrel if you don't get enough twist before the bullet reaches the end of the barrel. Since you give up distance of twist inside the barrel, you would be making up for it with the faster twist. Not sure if that's true, just what I thought in my head haha</div></div>
The only thing that would affect stability in relation to barrel length is if the barrel was so short(or long) that the velocity was substantially different. That inch or two is only going to change the velocity and thus the spin rate of the bullet by a very small amount. The stability of the bullet is based pretty much on its length and how fast its turning. There are online calculators out there that can tell you how fast you need to spin a certain bullet to keep it within theoretical norms.
Spinning the bullet faster than necessary doesn't really hurt accuracy unless you are shooting well beyond the range of most rifles or are using subpar components. Variations in jacket thickness can cause unbalance which will cause wobble, jackets too thin might fail, bullets not square and concentric will lose accuracy. Overstabilizing the bullet is more a problem with long range artillery than with rifles......
going with the 1-10 twist will give you more versatility if you can seat the light bullets out far enough to keep the bullet close to the lands. Some mags won't allow that so its one thing to think about in your decision. Being able to shoot the long heavies is nice sometimes but might not really gain you that much either unless you can get the velocity that makes it worthwhile. 220's in a .308 don't really make much sense but 190's are great.....1-10 or 1-11.25 should be fine for everything up to that in standard .308 bullets.
You must choose as you have to live with it...
Frank
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glazer1972</div><div class="ubbcode-body">1:10"</div></div>
Same.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: glazer1972</div><div class="ubbcode-body">1:10"</div></div>
Same.
Re: .308 twist rate?
just get a 10 twist it is the standard for 308 factory rifles i have shot 130gr HP progectiles out of 10 twists in 1/4" groups at 100 metres they work with light bullets and heavy projectiles aswell. If you are wanting to shoot heavy projectiles then just get a 10 twist the accuracy potential will come down to 2 things the quality of the projectile and ammo then the quality of the barrel and fitting that is it if it is a crap barrel with crap ammo the twist want be the main problem if the twist is to fast but the projectiles are perfect then it will still shoot well. the reason for tightening up the twist on shorter barrels like shorter than 20" is they can not achieve the muzzle velocity of a 26" pluss barrel of the same dimensions and quality so the projectile that is just stabalised in the long barrel will not be spinning as fast out of the shorter barrel at the lower velocity and would become unstable.
Just get a match barrel 10 twist and shoot it.
just get a 10 twist it is the standard for 308 factory rifles i have shot 130gr HP progectiles out of 10 twists in 1/4" groups at 100 metres they work with light bullets and heavy projectiles aswell. If you are wanting to shoot heavy projectiles then just get a 10 twist the accuracy potential will come down to 2 things the quality of the projectile and ammo then the quality of the barrel and fitting that is it if it is a crap barrel with crap ammo the twist want be the main problem if the twist is to fast but the projectiles are perfect then it will still shoot well. the reason for tightening up the twist on shorter barrels like shorter than 20" is they can not achieve the muzzle velocity of a 26" pluss barrel of the same dimensions and quality so the projectile that is just stabalised in the long barrel will not be spinning as fast out of the shorter barrel at the lower velocity and would become unstable.
Just get a match barrel 10 twist and shoot it.
Re: .308 twist rate?
1/10 is my choice, when there is one. It opens doors to heavy bullets, and also more latitude in bullet choice if you ever want to load up sub-sonic.
That said, my 1/12 Rem barrel handles 208gr AMax, and 220gr Matchking just fine.
1/10 is my choice, when there is one. It opens doors to heavy bullets, and also more latitude in bullet choice if you ever want to load up sub-sonic.
That said, my 1/12 Rem barrel handles 208gr AMax, and 220gr Matchking just fine.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MontanaMarine</div><div class="ubbcode-body">1/10 is my choice, when there is one. It opens doors to heavy bullets, and also more latitude in bullet choice if you ever want to load up sub-sonic.
That said, my 1/12 Rem barrel handles 208gr AMax, and 220gr Matchking just fine. </div></div>
it would be interesting to actualy measure the twist on these 12 twist barrels that apparently stabalise a 208 A Max as we have cut rifled match barrels that are definatly 12 twist that have no hole of stabalising them and Hornady states a 10 twist is required aswell. we have comp shooters using 9 to 10 twists with them and the 9 and 9.5 twists with 308's shooting to 1500 yards stabalise them the best a true 12 twist will never stabalise them out of a 308 at that range. I am sure a lot of these barrels are 10 twists stamped as 12's just for marketing as it is the standard.
I would love to see a barrel maker actualy measure the twist and confirm what they realy are.
I believe people are shooting 208's out of barrels marked 12 twist i just dont believe the manufactures if this is the case.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MontanaMarine</div><div class="ubbcode-body">1/10 is my choice, when there is one. It opens doors to heavy bullets, and also more latitude in bullet choice if you ever want to load up sub-sonic.
That said, my 1/12 Rem barrel handles 208gr AMax, and 220gr Matchking just fine. </div></div>
it would be interesting to actualy measure the twist on these 12 twist barrels that apparently stabalise a 208 A Max as we have cut rifled match barrels that are definatly 12 twist that have no hole of stabalising them and Hornady states a 10 twist is required aswell. we have comp shooters using 9 to 10 twists with them and the 9 and 9.5 twists with 308's shooting to 1500 yards stabalise them the best a true 12 twist will never stabalise them out of a 308 at that range. I am sure a lot of these barrels are 10 twists stamped as 12's just for marketing as it is the standard.
I would love to see a barrel maker actualy measure the twist and confirm what they realy are.
I believe people are shooting 208's out of barrels marked 12 twist i just dont believe the manufactures if this is the case.
Re: .308 twist rate?
1:10 in both my 16" DPMS and my 22" barreled M40A3 wantabe. My M40A1 has a 1:11.25 and shoots most everything well except the 147gr machine gun stuff and that pattern better resembles a cone of fire than a shot group. I used to have a Rem 1:12 cut to 18" and anything over 168gr did not print on paper near as well as the 168's or 155's.
1:10 in both my 16" DPMS and my 22" barreled M40A3 wantabe. My M40A1 has a 1:11.25 and shoots most everything well except the 147gr machine gun stuff and that pattern better resembles a cone of fire than a shot group. I used to have a Rem 1:12 cut to 18" and anything over 168gr did not print on paper near as well as the 168's or 155's.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wild_Bill</div><div class="ubbcode-body">just get a 10 twist it is the standard for 308 factory rifles i have shot 130gr HP progectiles out of 10 twists in 1/4" groups at 100 metres they work with light bullets and heavy projectiles aswell. If you are wanting to shoot heavy projectiles then just get a 10 twist the accuracy potential will come down to 2 things the quality of the projectile and ammo then the quality of the barrel and fitting that is it if it is a crap barrel with crap ammo the twist want be the main problem if the twist is to fast but the projectiles are perfect then it will still shoot well. the reason for tightening up the twist on shorter barrels like shorter than 20" is they can not achieve the muzzle velocity of a 26" pluss barrel of the same dimensions and quality so the projectile that is just stabalised in the long barrel will not be spinning as fast out of the shorter barrel at the lower velocity and would become unstable.
Just get a match barrel 10 twist and shoot it.
</div></div>
Bullet spins the same regardless of barrel length; faster twist gives you slower mv.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wild_Bill</div><div class="ubbcode-body">just get a 10 twist it is the standard for 308 factory rifles i have shot 130gr HP progectiles out of 10 twists in 1/4" groups at 100 metres they work with light bullets and heavy projectiles aswell. If you are wanting to shoot heavy projectiles then just get a 10 twist the accuracy potential will come down to 2 things the quality of the projectile and ammo then the quality of the barrel and fitting that is it if it is a crap barrel with crap ammo the twist want be the main problem if the twist is to fast but the projectiles are perfect then it will still shoot well. the reason for tightening up the twist on shorter barrels like shorter than 20" is they can not achieve the muzzle velocity of a 26" pluss barrel of the same dimensions and quality so the projectile that is just stabalised in the long barrel will not be spinning as fast out of the shorter barrel at the lower velocity and would become unstable.
Just get a match barrel 10 twist and shoot it.
</div></div>
Bullet spins the same regardless of barrel length; faster twist gives you slower mv.
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Turk</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wild_Bill</div><div class="ubbcode-body">just get a 10 twist it is the standard for 308 factory rifles i have shot 130gr HP progectiles out of 10 twists in 1/4" groups at 100 metres they work with light bullets and heavy projectiles aswell. If you are wanting to shoot heavy projectiles then just get a 10 twist the accuracy potential will come down to 2 things the quality of the projectile and ammo then the quality of the barrel and fitting that is it if it is a crap barrel with crap ammo the twist want be the main problem if the twist is to fast but the projectiles are perfect then it will still shoot well. the reason for tightening up the twist on shorter barrels like shorter than 20" is they can not achieve the muzzle velocity of a 26" pluss barrel of the same dimensions and quality so the projectile that is just stabalised in the long barrel will not be spinning as fast out of the shorter barrel at the lower velocity and would become unstable.
Just get a match barrel 10 twist and shoot it.
</div></div>
Bullet spins the same regardless of barrel length; faster twist gives you slower mv. </div></div>
did you miss the part where a shorter barrel has a slower muzzle velocity with the same ammo. doesnt the projectile spin rate directly corespond to the twist x the velocity?
Make sure you actualy read the post or understand before arguing.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Turk</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wild_Bill</div><div class="ubbcode-body">just get a 10 twist it is the standard for 308 factory rifles i have shot 130gr HP progectiles out of 10 twists in 1/4" groups at 100 metres they work with light bullets and heavy projectiles aswell. If you are wanting to shoot heavy projectiles then just get a 10 twist the accuracy potential will come down to 2 things the quality of the projectile and ammo then the quality of the barrel and fitting that is it if it is a crap barrel with crap ammo the twist want be the main problem if the twist is to fast but the projectiles are perfect then it will still shoot well. the reason for tightening up the twist on shorter barrels like shorter than 20" is they can not achieve the muzzle velocity of a 26" pluss barrel of the same dimensions and quality so the projectile that is just stabalised in the long barrel will not be spinning as fast out of the shorter barrel at the lower velocity and would become unstable.
Just get a match barrel 10 twist and shoot it.
</div></div>
Bullet spins the same regardless of barrel length; faster twist gives you slower mv. </div></div>
did you miss the part where a shorter barrel has a slower muzzle velocity with the same ammo. doesnt the projectile spin rate directly corespond to the twist x the velocity?
Make sure you actualy read the post or understand before arguing.
Re: .308 twist rate?
Since when does Velocity affect spin rate? No need to get uncivil; and perhaps you missed the part about faster twist w/ a shorter barrel gives you an even slower barrel? What happens when transonic?
Since when does Velocity affect spin rate? No need to get uncivil; and perhaps you missed the part about faster twist w/ a shorter barrel gives you an even slower barrel? What happens when transonic?
Re: .308 twist rate?
Does the faster twist rate actually=slower MV? I think it may slow the bullet, but that increases pressure, gaining velocity (I know my 1:10 Rock runs faster than the same length 1:11.25 Rocks).
Does the faster twist rate actually=slower MV? I think it may slow the bullet, but that increases pressure, gaining velocity (I know my 1:10 Rock runs faster than the same length 1:11.25 Rocks).
Re: .308 twist rate?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Turk</div><div class="ubbcode-body">Since when does Velocity affect spin rate? No need to get uncivil; and perhaps you missed the part about faster twist w/ a shorter barrel gives you an even slower barrel? What happens when transonic? </div></div>
Slower velocity does affect spin rate (RPM)
I think we can all agree on the fact that there is 12 inches per foot. Now, since we measure velocity in feet per second it's pretty simple.
For example:
A bullet @ 2650 FPS in a 1/12'' barrel has a RPM of 31,800
2650*12 = 31,800
A bullet @ 2500 FPS in a 1/12'' barrel has a RPM of 30,000
2500*12 = 30,000
Now if dealing with a 1/ 11.25'' twist, you need a multiplying factor of 1.067 from 12 inches divided by 11.25 = 1.067
So a bullet @ 2500 in a 1/11.25'' barrel has a rpm of 32,010
(2500*12)1.067 = 32,010
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Turk</div><div class="ubbcode-body">Since when does Velocity affect spin rate? No need to get uncivil; and perhaps you missed the part about faster twist w/ a shorter barrel gives you an even slower barrel? What happens when transonic? </div></div>
Slower velocity does affect spin rate (RPM)
I think we can all agree on the fact that there is 12 inches per foot. Now, since we measure velocity in feet per second it's pretty simple.
For example:
A bullet @ 2650 FPS in a 1/12'' barrel has a RPM of 31,800
2650*12 = 31,800
A bullet @ 2500 FPS in a 1/12'' barrel has a RPM of 30,000
2500*12 = 30,000
Now if dealing with a 1/ 11.25'' twist, you need a multiplying factor of 1.067 from 12 inches divided by 11.25 = 1.067
So a bullet @ 2500 in a 1/11.25'' barrel has a rpm of 32,010
(2500*12)1.067 = 32,010
Re: .308 twist rate?
1/10 twist at 3000 fps mv will have twice the RPS, as a 1/10 twist at 1500 fps mv.
That influences stability.
1/10 twist at 3000 fps mv will have twice the RPS, as a 1/10 twist at 1500 fps mv.
That influences stability.
Re: .308 twist rate?
ok here is a comparison if you want to shoot a 208 A amx out of a 308 the twist reccomended is a 10 twist because of the velocity however if you try to shoot the same projectile at 1000fps from the exact same rifle the 208 will likley not stabalise that projectile because it is not spinning fast enough to stabalise the projectile and an 8 twist is required to achieve that. This is why people usualy shoot a lighter or shorter projectile when they shoot sub loads to make sure that they will stabalise.
I have a factory Rem barrel that was a 7mm rem mag and would stabalise the 175gr MatchKings and 180gr Bergers but i chopped it back to 17" and fitted it to another rifle as basicaly a 7mm whisper it will not even stabalise the 162 A AMx at 1000 fps the longest projectile it will stabalise is a 154gr SST.
This is because the projectile is not spinning as fast as it was when it was launched 3 times as fast it has 1/3rd the spin as it used to because of the lighter calibre but it is the exact same barrel.
There are 2 factors in stability that we realy need to worry about first is the twist and seccond is the velocity that we can achieve together they will give us the required spin on the projectile to stabalise it at a set elevation.
ok here is a comparison if you want to shoot a 208 A amx out of a 308 the twist reccomended is a 10 twist because of the velocity however if you try to shoot the same projectile at 1000fps from the exact same rifle the 208 will likley not stabalise that projectile because it is not spinning fast enough to stabalise the projectile and an 8 twist is required to achieve that. This is why people usualy shoot a lighter or shorter projectile when they shoot sub loads to make sure that they will stabalise.
I have a factory Rem barrel that was a 7mm rem mag and would stabalise the 175gr MatchKings and 180gr Bergers but i chopped it back to 17" and fitted it to another rifle as basicaly a 7mm whisper it will not even stabalise the 162 A AMx at 1000 fps the longest projectile it will stabalise is a 154gr SST.
This is because the projectile is not spinning as fast as it was when it was launched 3 times as fast it has 1/3rd the spin as it used to because of the lighter calibre but it is the exact same barrel.
There are 2 factors in stability that we realy need to worry about first is the twist and seccond is the velocity that we can achieve together they will give us the required spin on the projectile to stabalise it at a set elevation.
Re: .308 twist rate?
http://www.6mmbr.com/barrelfaq.html#24640
I assume if one sees it as a function of time you are correct; but the bullet spins an x amount of revolutions for a given distance if I am not wrong?
http://www.6mmbr.com/barrelfaq.html#24640
I assume if one sees it as a function of time you are correct; but the bullet spins an x amount of revolutions for a given distance if I am not wrong?
Re: .308 twist rate?
sorry you are not getting it as soon as the projectile leaves the bore it no longer travels say 1 foot forward for a full revolution like you are thinking the velocity imparted on the projectile that is required to retain stability is measured in revs per minuite and you might got a slightly faster velocity with less twist but if shooting heavy projectiles out of match barrels the diference between an 11 and 10 twist would be very small and either could be faster than each other because of the bore finish or even the quality of the steel. a projectile still requires velocity and twist to stabalise just take the other peoples word for it if you dont believe me.
sorry you are not getting it as soon as the projectile leaves the bore it no longer travels say 1 foot forward for a full revolution like you are thinking the velocity imparted on the projectile that is required to retain stability is measured in revs per minuite and you might got a slightly faster velocity with less twist but if shooting heavy projectiles out of match barrels the diference between an 11 and 10 twist would be very small and either could be faster than each other because of the bore finish or even the quality of the steel. a projectile still requires velocity and twist to stabalise just take the other peoples word for it if you dont believe me.
