Ruger American .223 1/8 twist and accuracy.

[SARuger]

I have one of these, Its a very nice shooting rifle but.....it likes heavy bullets. Mine stabilizes 63-69 grain bullets better than the lighter or heavier bullets. I have tried 55g(the lightest I have tried) and its all over the place, same with 77g(the heaviest I have tried)

The charts here (http://thefiringline.com/forums/showthread.php?t=530927) say that it should like the 45grain bullets the best but Sierra/ Berger says 75-80grain? Or have I misread this info?

I'm getting into re-loading and I want to get the most out of this RAR that I can for target/varmint.

Suggestions?

[603Country]

I'd try another bullet and another powder, if you reload. If you don't reload, start doing so.

My Ruger 77 is a 1 in 9 twist. It loves 55 gr bullets, but with H335 and 40 gr Nosler BT's (load near max) it loves the little bullet too. Oddly enough, in an article about the 223, and I forget exactly what the article was about, they shot a lot of various weight bullets and everything shot great but the 45 grainers of various makers. Try the 40's and the 50's and H335.

[Jimro]

SARuger, you misread the info. 1:8 should be 75 to 80gr although it should be fine shooting lighter bullets as well.

Suggestions for the rifle:
1, ensure the scope and rings are tight
2, try some commercial ammo, if none of the commercial loads shoot tight, replace the scope.

Suggestions for the handload:
1, prep your brass by annealing, full length sizing, and trimming.
2, do an OCW load workup using a 75 to 80gr match bullet and either Varget, H4895, or IMR4166.

Hope this helps identify your issues.

Jimro

[Sappyg]

I've had some of the worst groups I've ever fired through my RAR. Conversely I've had the very best groups ever through the same rifle. You just have to be willing to keep trying new loads until you find the right combo.
For lighter bullets you might find that a different powder is better suited. Not that it's the best but I use 748 for 55 grain wt. heavier bullets in the mid 60 gr class I like imr 4895. I've basically settled on the 65 gr Sierra game king pushed along by 23.5 gr of 4895 for an all around load for my RAR. That rifle throws that load like nothing else and I feel like I'm getting the most out of the rifle when I'm using it.

[SARuger]

Mine likes 69g factory loads but I will try some lighter stuff as well.

I have a couple pounds of RL-15. Have you had any experience with that powder and the .223?

[Ifishsum]

RL-15 is my favorite powder for the .223 and heavier bullets (69+). You could do a lot worse IMO, although I haven't really tried it for lighter ones.

[Jimro]

Reloader-15 is fine for 75 and 80gr bullet in 223.

Look for an accuracy node around 24 grains. Alliant lists 24.1gr max charge with 77gr SMK, and 25.5gr max charge with 69gr SMK. reduce by 10% and work up.

Jimro

[wpsdlrg]

Every rifle is different. Yours, with a 1:8 barrel, just happens to not like light bullets as much as heavier ones. Another identical barrel might do better with the lighter pills. It also might do better with lighter bullets, with lighter LOADS. You have the twist to stabilise almost any bullet you want to try, but it might be spinning the lighter ones too fast with the loads you are using. Go lighter, if you haven't already - it might help.

My 1:9 Stevens (Savage), likes everything up to 68-69 grains, but nothing heavier. That is generally to be expected with a 1:9 twist. But, it likes the 68-69 grain bullets by far best of all. It shoots 55 grainers very well, but not as well as 68-69 grainers. Less than 55 grains....the lighter you go, the less it likes them.

Go figure. At least I found what it likes - and it sort of makes sense - so I can load to that standard.

[SARuger]

I scored some IMR4895, last bottle on the shelf today. Pricey stuff at $40 a pound. But I have options now :D

[JohnKSa]

The charts here say that it should like the 45grain bullets the best but Sierra/ Berger says 75-80grain? Or have I misread this info?The charts should give you an idea of what a given twist will stabilize and what it won't. Don't try to analyze the specific group sizes, that's not going to provide useful information. All the graphs show is acceptable accuracy (say under 3" or so) which means that the bullets were stabilized, or unacceptable accuracy (over 3") which means that the bullets weren't stabilized.

I've added a note to the post to help explain.

Generally speaking, if we're talking about conventional lead-core, copper-jacketed bullets, 1:8 twist should stabilize bullets up to 77 grains, maybe a little heavier--at least out to 100 yards which is the distance used in the testing.

If you're talking about monolithic copper bullets, steel core bullets, or any other bullets that are unusually long for their weight then you may have to go lighter (or to a faster twist) in order to get proper stabilization. Also, if you stretch the range, have a very short barrel (resulting in low muzzle velocity and therefore slower spin), are shooting very light loads (again low muzzle velocity/slower spin), or are shooting in very cold conditions (which lowers the muzzle velocity/slows spin), a bullet that is marginally stabilized under normal conditions may not stabilize.

If a rifle stabilizes a given weight bullet, it should also stabilize lighter bullets, although it may spin them faster than is ideal. That shouldn't cause problems unless the bullets are poor quality in which case the faster spin may amplify any imbalance issues/inconsistencies or in the extreme case where the bullets actually come apart from being spun too fast.

[handlerer2]

The Speer Manual has had a comment about light varmint bullets and high MV, since I started reloading in 1976. A bullet fired from a 1/7" at 3500 fps is rotating at 330,000 rpm. More centripetal force than their varmint bullets are designed for.

I don't believe this means the bullet is of inferior quality.. It just not not made for the heat, pressure, and angular momentum found in the fast twist barrel. IMO.

[JohnKSa]

I don't believe this means the bullet is of inferior quality...Right, there are two possible problems when you spin a bullet faster than you need to:

1. If the bullets are "poor quality ... the faster spin may amplify any imbalance issues/inconsistencies".

-OR-

2. "The extreme case where the bullets actually come apart from being spun too fast."

[Mobuck]

I have 1-8 and 1-9 barrels(16") that are very accurate with 40-55 grain factory loads but not all are top-notch with bullets heavier than 60 grains. On the other hand, I have a 1-9 (20") that is extremely accurate with 69 BTHP. Really no true pattern directly related to twist/bullet weight in the 1-8/1-9 rates.