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I went through 2 barrels without satisfaction for accuracy. For my 3rd, I went with Alexander Arms, and am happy. I would have gotten the criterion, but for that project it needed to be a 20", which Criterion I guess doesn't make, since all I see from them are 18 and 22. If your project is more general, and 18" will do - then I'd get that Criterion deal.
I will say, I found some quotes from Bill Alexander here, that I found very helpful:
I will say, my 20" Alexander Arms with 1/9, shoots well; and I too found my 1/8 barrels temperamental (but then, mine weren't exactly Ljija BBL's either).
I will say, I found some quotes from Bill Alexander here, that I found very helpful:
When we were first working on the Grendel we followed what everyone said about 6.5 calibers and made the barrels with 8 twist rifling. Some barrels would shoot but more often than not the groups were open and the guns were tempremental. One of the very early test rigs had run a 9 twist and it actually shot well despite a less than optimum chamber so out of frustration we ignored conventional wisdom and build some 9 twist units at 24" and 20" barrel lengths. The change in accuracy for the group as a whole was unquestionable. Subsequent production of 9 twist barrels has proven that this is optimum for the caliber.
One of the contributors to the 9 twist is actually the Grendel itself. Pressure limits the ability to slug the bullet to the grooves and the case capacity holds the round to lighter bullets. The 168 grain roundnose nickel steel projectiles are simply not a consideration any more than the 142 and 155 grain SMKs
We have tested barrels as short as 14.5" in 9 twist (not recommended use 1:7.5 this short) with projectiles up to 152 grains and both accuracy and stability are maintained. Equally we have run 9 twist barrels out to 1600 yards (12" group) and the round remains stable and it would appear accurate through the transition velocity. Longer 8 twist barrels often demand velocity reduction for best accuracy
It is our conclusion that the 9 twist offers the best solution for the Grendel for barrels of 20" and longer while the 18" and shorter barrels thrive on 7.5 twist.
One of the contributors to the 9 twist is actually the Grendel itself. Pressure limits the ability to slug the bullet to the grooves and the case capacity holds the round to lighter bullets. The 168 grain roundnose nickel steel projectiles are simply not a consideration any more than the 142 and 155 grain SMKs
We have tested barrels as short as 14.5" in 9 twist (not recommended use 1:7.5 this short) with projectiles up to 152 grains and both accuracy and stability are maintained. Equally we have run 9 twist barrels out to 1600 yards (12" group) and the round remains stable and it would appear accurate through the transition velocity. Longer 8 twist barrels often demand velocity reduction for best accuracy
It is our conclusion that the 9 twist offers the best solution for the Grendel for barrels of 20" and longer while the 18" and shorter barrels thrive on 7.5 twist.
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