375 cheytac barrel twist.

[desertHK]

All these readings about the 375 bullets is making my head hurts. I know the 375 ballistic is more superior to the 408 cheytac. But with a 1:11.5 twist, what kind of bullets can I shoot? Am I going to be able to reach 3000 yards with that twist? Reason I ask is I already have a 338 LM that can shoot out to about 2000 Yards and a 50 BMG that can stay supersonic out to 3000 yards where I am. I just need some thing a bit more accurate than the 50 BMG. Any help is greatly appreciated guys.

 

[Louis Corkern]

Re: 375 cheytac barrel twist.

Desert:

50 that stays supersonic at 3000 yards?? Here is brief ballistic data for a few of the common 50cal rounds:
1. 750gr Amax--NOT suitable for material neutralization
1800m super sonic range with 2650fps MV
15m Max ordinate @ 1800m
3m target has danger space of 71m @1800m

2. Mk211 Mod-0--Suitable for light skinned targets..NOTE: Explosive will not detonate if impact on target is NOT super sonic
1400m super sonic range with 2675fps MV
30m Max ordinate @ 1400m
3m target has danger space of 87m @1400m

3. M20 APIT
1500m super sonic range with 2650fps MV
35m Max ordinate @ 1500m
3m target has danger space of 81m @1500m

4. M8 API
1500m super sonic range with 2650fps MV
37m Max ordinate @ 1500m
3m target has danger space of 77m @1500m

5. C44 AP-T
1600m super sonic range with 2175fps MV
47m Max ordinate @ 1600m
3m target has danger space of 70m @1600m

The 11.5 twist rate is specifically designed for the 350gr Lost River Ballistic Technologies solid copper/nickel alloy projectile.
LRBT has been "out business" for couple years so now you get those projectiles from Jamison Internation (Cheytac).

Thanks

 

[desertHK]

Re: 375 cheytac barrel twist.

Don't disagree with you Later. 3K for a 50 BMG is a big stretch to say the least. I have the higher altitude to help with staying supersonic. But again, that's the ceiling of that ballistics.

I would like a Cheytac. Took your advice and favor the 375 over the 408. My only problem is what twist rate to get and be able to shoot the readily available bullets. I want to be able to stretch it out much further than what my 338 LM is capable of.

What twist rate would you recommend then?

 

[Louis Corkern]

Re: 375 cheytac barrel twist.

I would say if your going to shoot the 350gr solids go with 11.5 twist if you wanting something that is KNOWN to work.

But I will then be open and honest and say that I do not think enough "experimenting" has been done in regards to other twist rates lol. That is reason I ordered an 8 twist with LRBT bore pattern that I was gonna build a short barrel 375 on. Was gonna use the faster twist to make up for some of the stabilization lose due to MV decrease.

IMO your barrel twist plays second fiddle to your projectile choice.

Thanks

 

[desertHK]

Re: 375 cheytac barrel twist.

Much appreciated Later.

 

[Wild_Bill]

Re: 375 cheytac barrel twist.

Hi just call up Lawton nad have them spec the twist for you i believe a 12 is what they mostly use, Or just get the 11.5 it will make no difference to your shooting at all having it slightly faster.

 

[djd]

Re: 375 cheytac barrel twist.

CheyTac designed the 375/350 gr. solid the same as the 408/419 using Prodas software. The program said 11.5 twist is optimal for that bullet. We forwarded the Prodas spec.s and groove configuration on to Lawton for all CheyTac barrels.

That twist was designed for the 350 gr. solid, but we've shot all other .375 commercial bullets from 260-300 gr. with that twist, and they did OK. The 300 gr. Nosler Partiton being the best "off the shelf" hunting bullet to date for accuracy.