.223 mauser action 1:9 projectile weight

[notropis]

This fall I bought a new Savage Axis II in .223 Rem. The only modification is a new stock. Hornady FMJ work well in my AR's so I thought I'd see what kind of accuracy I could get with the new Savage. Using H335 powder and starting at "start load" working up in .5 grain increments, I could not get decent accuracy.

By chance last week, I wanted to give Nosler Varmageddon projectiles at 62 grains a try. I coupled the Nosler projectiles with Alliant Reloader 15 power (at start load) and they were touching at 100 yards. Great accuracy!

This week I decided to try Nosler Varmageddon projectiles at 55 grain weight with H335. Starting at "start" and again working up to max, I had very poor accuracy. I then shot 62 grain Noslers again with Reloader 15 and had great accuracy.

This 1:9 twist rifle has not shot any 55 grain projectile with good results. What should I make of this experience? Keep trying different 55 grain projectiles? Used slower powders with 55 Grain projectiles? Give up on 55 grains and focus on heavier projectiles?

 

[200Apples]

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There is some discussion of this topic here:

Is 1 in 9 twist really too slow for heavy 5.56 rounds?


A family member just purchased a CZ527 Carbine in .223 Win (18" bbl length) that has a 1:9 rate... he had been asking me a question similar to yours. I pointed him in the direction of that link.

Good luck to you! and safe shooting.

 

[notropis]

Good Link Apples. Thanks for the read.

 

[Clint M]

I wouldn't make much over it myself. I have shot 1-9 twist ar that would hold .25" or less 10 shot groups at 100 yards this was walmart winchester 40gr varmint rounds. I had a Copper at the time as well 1-12 twist ( I think) Sierra sent me a good many bullets to test in both guns, when I emailed Sierra the man I was talking with said that my results were a mirror to their results. From what I seen the faster twist does not have as much effect on groups as long as it stabilizes, also keeping in mind the limits of the bullet= velocity/rpm etc.

Most of my test was around 69gr SMK... but I tested that against 35gr-60gr Sierra bullets as well as what I had on hand. What my end results where 40gr bullets polymer tipped out to around 300 would out shoot anything overall 52gr smk and other match bullets were a close twin in group sizes, 60gr v-max is another great bullet. For some reason 40gr and 60gr (not counting match bullets) were the best weight/shooting bullets in 3 test guns.

I lost every bit of the info I had with a computer crash. Sierra, and Cooper were outstanding to deal with as Sierra sent me load data, bullets, electronic charts I just had to fill in. I shot so much I was worried I would shoot the barrel out of my Cooper, however they said they would rebarrel free of charge if I could do so... I never came close even with around 2,000 rounds down the tube.

 

[witchhunter]

A 9 Twist should shoot bullets heavier than 55's easy peasy! Maybe even 69's....experiment. Does it shoot 50's better? You can shoot 55's with a 14 twist usually.

 

[notropis]

I did try a few lighter projectiles but did not do complete powder work up's with them. The lighter projectiles were no more accurate than the 55 grains.

I will load up some 69 grain SMK's and see how they do. I'll also report back once I get back to the range.

I think it's a little odd my 1:9 AR's do great with 55 grain, but my Mauser action won't. Perhaps something to do with lost gas/pressure in the AR's?

 

[Art Eatman]

Sounds to me as though it's less about the twist than it is about the combination of bullet/powder affecting the barrel harmonics. Different brand of 55-grain bullet and/or different brand of powder might change things to a good result.

 

[sirgilligan]

I have a 1 in 9 twist micro-mauser action CZ 527 Varmint.
I have seen excellent results with factory ammo and I have shot one hand load my brother loaded up.

 

[sirgilligan]

 

[sirgilligan]

Ignore shot at top. There were several of us taking turns shooting. The three together is what I am showing here.

 

[sirgilligan]

 

[sirgilligan]

My Uncle shot one 35 grain round and said he was aiming at the bulls eye. The target tore because it was taped to an old 50 gallon drum that was shot up badly and there was a big hole directly behind the target, so it was like the target was just suspended in air so to speak.

 

[sirgilligan]

Here is the hand load.

 

[sirgilligan]

In summary, those shots are from a CZ 527 Varmint 1:9 twist with a micro-mauser action. They were all shot off the hood of a Ford Ranger (that might make a difference) with a couple of sand bags to adjust with. The rifle was fired by seven different people. Everyone experienced the same accuracy. Some shots were fired with the trigger set, some where not. The projectiles were 35 grain, 55 grain, 62 grain, 68 grain, and 75 grain. There were no signs of instability, no key holes, nothing like that. The point of impact would change vertically slightly but nothing to cause any concern. There was no concern for barrel temperature, we started with the first shot and kept firing for over an hour, so the vast majority were from a hot barrel, just the pauses of going down range to collect the target and stuff like that.

 

[ford8nr]

Notropis, interesting results. I have an Axis 'project' rifle I bought this fall. I have yet to get 55 or 60gr bullets to group good. 68gr Hornadys are very consistent. In my rifle the 60gr shoot about 8" right of the 68gr. Right now with a mild load I'm shooting 5 shot / 100yd groups of 1.3" off a front bag.

 

[notropis]

Well, I guess I should qualify my unsatisfactory accuracy comment. The 55 grain projectiles do ok. Good enough to kill a coyote at 200 yards. The groups look a lot like sirgilligans. Once I used starting loads with 62 grain projectiles and slower powder, ten shot groups were the size of a nickel at 100 yards if you ignore my poor breathing shots. It was like night and day.

I loaded up some SMK's tonight with three different powders and will try them soon.

I also loaded more 62 grain Noslers but I went below starting powder charge as I think I'm "over stabilizing" these short, light projectiles. Groups opened up as powder increased.

 

[sirgilligan]

That's great news. Thanks for the update.

 

[oldfortyfiveauto]

I've not had much luck with bullets heavier than 60grs in 1:9 twists. I've had 69gr bullets keyhole. Since my main focus is prairie dogs it's not an issue with me.

 

[Clint M]

69gr smk is does not hit peak performance until 300 yards that's their design, a 52gr smk or 40gr poly tip will shoot better. Barrels can be picky consider yourself lucky to find 3 weight bullts shoots .5 MOA. My experience has been 40gr poly tip (blitzking, v-max, b-tip) various 52match and the 60 gr v-max, out of each of these you will need to find what works best in your rifle. 69r smk 300 yards a outstanding bullet exceptions to every rule other than that your looking at a custom barrel set up for a specific bullet.

As I said above so many options and many I left out I had some custom 52gr swagged 22 rimfire cases over a lead core that would out shoot any of the brand name match 52gr BUT not over a sustained period=flyers. I was really into precision shooting and loved it. Now the killer if your really after itty bitty hols lots changes kills everything, Sierra sent me 5k lots with some lot samples to test against. They would not hold in the same group however powder charge and seating depth brought the same results.

Do as much research as possible some barrels prefer some bullets, all it takes is time money to find out which so. I have come to accept this, still I have my fall back bullets to test a new rifle.... simple as charting twist rate to bullet weight/vld length then start picking your poison... find tune after you find a bullet that show promise but don't overlook a bullet/load that doesn't one hole on first load testing.

 

[notropis]

Just to follow up. The 69 SMK perform as accurately as all the 55 grain projectiles used previously. They performed best with Reloader 15 powder @ 22.4 grains. The 69 grain SMK did stabilize fine, they did not impress me with this rifle. I used three different powders at three different powder weights.

The Nosler Varmageddon 62 grain however is making one ragged hole when I go below start charge with Reloader 15 powder. 22 grains of powder has been my most accurate load with above projectile.

I'm not sure what to make of all this. I love the Nosler Varmageddon projectiles, but I'd like to be able to push them a little faster I guess. One thing is for sure, I'm accumulating a large inventory of projectiles that don't perform worth a darn for this rifle

 

[DRYHUMOR]

Try 69gr SMKs with some Varget, start 23.4 grains or so and work up.

 

[notropis]

Varget was one of the powders I tried with the 69 grain SMK. With this particular rifle, Varget along with the 69 SMK was the least accurate load made.

 

[Johnny_B_Goode]

I shoot 62 gr Federal Mod 0 ammo from my DPMS with a 20" barrel and a 1:8 twist. Mod 0 is not the most accurate ammo you can buy but it really performs. I don't see how you are going to have issues with your 1:9 twist barrel. Accuracy might be degraded a little bit but you are not going to have key holing or anything totally unacceptable with your 223 rifle. My wife's Colt LE6920 has a true 1:7 twist barrel. The difference in accuracy is so minute you would have to shoot off a bench and break out the calipers to tell the difference in accuracy if there is any difference.

 

[greyling22]

some guns are finicky. I have a mini mauser in a 1:10 or 12 twist that will shoot a 50 grain bullet really well, but sprays 55grainers all over the place, even though a 1:10 or 12 should still stabilize a 55. who knows.