Best twist rate in AR barrel for basic factory ammo with 55 grain bullet?

**jack76590** · January 14th, 2023, 05:21 PM

Originally Posted by bigandy1966

I have even found some specific manufacturers perform better in some barrels than others.
Some twist/ bullet weights/ manufacturers combinations would buck the conventional wisdom depicted in the graph.
I have a .270 Remington 700 Adl that will shoot nickle sized groups with cheap ass Remington coreLokt 130 grains off the bench, all day long, but winchester or federal of the same bullet weight/ loads would go +/- 4-6" @100yds, some would even be premium hunting ammo
Find what the rifle likes the best.
Some guys who handload tweak the loads up or down to get the best performance.
One Guy at the range fire forms the brass in one specific rifles chamber and keeps that brass with that rifle and loads it to an exact recipe

I have been stocking up on some ammo from other manufacturers with differing bullet weights. Will try out in the Spring. Mainly Norma who had some decent mail-order prices with free shipping for over $149 orders. But now I don't see the same deals on Norma website.

**jack76590** · January 14th, 2023, 05:29 PM

Originally Posted by Palerider

Are you using a shooting rest/vice? If not the difference in your scopes could be contributing to group size as well. I find there*s a big difference between 4 and 9 X when you*re trying for precision and using bags only. Can you put higher powered scope on one of the other uppers and try again?

In past I used sandbags, but I recently bought a shooting rest. Looking back I did put on 12X scope on 1-7 twist PSA rifle just to test accuracy, did not sight in. This was one of PSA upper with FN premium barrel that I think chrome lined. Still bad accuracy. It could be the trigger, at least partially. I recently bought a Gissele two stage trigger and put on lower to be roaming lower to test accuracy. Want to eliminate poor trigger as potential problem.

**jack76590** · January 14th, 2023, 05:31 PM

Originally Posted by ShadeRabbit

Pretty much exactly what I'm getting with 1:7 PSA upper. Dog-crap accuracy. A guy at the range told me it's because PSA does not lap in their barrels, so that might be part of it in addition to the bullet grain.

One PSA upper (1-7 twist) that gave poor accuracy had what PSA said was premium FN barrel. I think barrel is chrome lined. I think FN in same general area as PSA.

**fritz1919** · January 14th, 2023, 10:27 PM

While I would not have subscribed to this theory 20yrs ago, I can now go with "I'm not sure it goes like that anymore." I'm talking about the certain twist, certain bullet weight rule. My last BYO was a 1-7. A Ballistic Advantage 16" mid length barrel (that I'm pretty sure I over torqued (one shim, too much, two shims, too little)). With 55gr bulk Hornady bulk bullets (for handloads), at 50yds the holes are often touching. Now that is with a fixed 3x - not irons. At 100yds I can often (not always) keep a group in 2.5" Same 3x glass. I feel confident that with a higher power scope, the rifle would do moa. My eyes just can't pull it off anymore with 3x at 100yds.

I think my BYO with this particular combination of parts goes to show that any given bullet might shoot well with any given barrel. Within reason, of course. Good technique and a decent rest with some good bags are a good way to remove a lot of human error. Then, some different brand 55's. Then, heavier bullet.

Either way fellas, 6" groups? No rifle, or upper built today should shoot that poorly. I'd be puttin a hold on that charge. At least till you can try some other loads.

Good luck. I'm interested in hearing how this shakes down. Hope to hear about some good groups.

**ShadeRabbit** · January 15th, 2023, 01:26 AM

Originally Posted by fritz1919

Either way fellas, 6" groups? No rifle, or upper built today should shoot that poorly. I'd be puttin a hold on that charge. At least till you can try some other loads.

Good luck. I'm interested in hearing how this shakes down. Hope to hear about some good groups.

I don't like the accuracy issues, but I can't complain at all about PSA reliability. Accuracy is secondary to reliability for me. I also bought the cheapest upper PSA offers. I'm content with "minute of man" accuracy, shooting from the bench without sandbags and with no optic. It's annoying, but I'm not really upset.

**ray h** · January 15th, 2023, 05:06 PM

Everything I own is 1/7 but I think 1/8, all else being equal, is probably the best overall. That said, I've got one PSA nitride 16" FF rifle that gave me a good solid sub 1MOA on one particular day shooting 62gr. Fiocchi.