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Does anyone know if the LWRC 1:10 twist barrels show higher pressures than 1:11 twist barrels for reloading? I'm currently working on 110 gr hollow points and up next will be 130 gr but I wanted to know if the LWRC barrel will have increased pressure.

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Should be fine
 

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The 1:10 vs 1:11 issue is most easily resolved by noting the 223/5.56 rifles run from 1:7 to 1:12...and survive just fine.
 

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The 1:10 vs 1:11 issue is most easily resolved by noting the 223/5.56 rifles run from 1:7 to 1:12...and survive just fine.
It was more about the bore area and engraving force. 10 twist 6 groove barrels with a 50:50 L-G ratio do not have the bore area that the Douglas 10 twist 4 groove that Murray used to set the specs do. Back in 04-06 they were pushing the loads as hot as possible to show the military that there was a lot of performance to be had. Now all of the factory ammo being produced can be shot in a SAAMI chamber rifle with 10 twist 6 grooves and a 50:50 L-G ratio. Bottom line is the factory ammo being produced now has been watered down to work in the worst spec barrels.

http://www.dtic.mil/dtic/tr/fulltext/u2/a431357.pdf
CONCLUSIONS
1. The baseline heptagonal barrel will exhibit peak chamber pressures about 15 to 20%
higher than the same cartridge loaded in a standard M240 barrel. This is due primarily to
the increased resistance pressure early in the in bore travel of the projectile.
2. The increase in peak chamber pressure could be reduced by either increasing the free run
of the projectile prior to the start of engraving or by reducing the forcing cone angle in the
barrel.
3. A slight decrease in resistance force was observed for the 2.5 deg half angle forcing cone
compared to the 1.2 deg half angle forcing cone found on the M240 barrel baseline. It is
believed this difference is due to a reduction in the plastic deformation of the M80
projectile in the 1.2 deg barrel.
4. The addition of lubrication to the M80 projectile exterior increased the engraving force in
the baseline M240 barrel with 1.2 deg half angle forcing cone, while it decreases the
engraving forces in the 2.5 deg half angle forcing cone barrel. Likewise the push force
standard deviation increased with lubrication in the 1.2 deg half angle forcing cone, and
decreased in the 2.5 deg half angle forcing cone.
5. Projectile construction and elastic modulus appear to play significant roles in the
resistance pressure of small caliber projectiles.
 

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Does anyone know if the LWRC 1:10 twist barrels show higher pressures than 1:11 twist barrels for reloading? I'm currently working on 110 gr hollow points and up next will be 130 gr but I wanted to know if the LWRC barrel will have increased pressure.

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A couple of ways to think about it. You could have a barrel that produces a little higher pressure that makes more velocity with less powder(think factory ammo) or you could have a barrel that produces less pressure and needs more powder to reach the same velocity. What is your limitation, powder capacity or powder burn rate and explosive force?
Without extensive testing it would be tough to say which would get you what you want and IMO you will need to work up the loads in any barrel to get the results you want.
 

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It was more about the bore area and engraving force. 10 twist 6 groove barrels with a 50:50 L-G ratio do not have the bore area that the Douglas 10 twist 4 groove that Murray used to set the specs do. Back in 04-06 they were pushing the loads as hot as possible to show the military that there was a lot of performance to be had. Now all of the factory ammo being produced can be shot in a SAAMI chamber rifle with 10 twist 6 grooves and a 50:50 L-G ratio. Bottom line is the factory ammo being produced now has been watered down to work in the worst spec barrels.

Don't disagree with your statement, but the OP was specifically asking about any real performance difference in LWRC barrels, which I assume will not have the issues you stated.
 
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