bullets fragmenting??

[utahyote]

Guys I am having a new gun built for coyote hunting it will be a 22-250 AI with a 8 twist barrel. I was planning on shooting 60 grain berger match varmints out of it. Question is do you think I will get bird shot with these or should they hold together?

 

[BuzzBoss915]

Re: bullets fragmenting??

I own two 22-250 Ackleys.

First, the usually overlooked question is; what purpose is this rifle to be used?

Most are used as predator guns. That is my purpose.

Second question, day hunting, night hunting, long range or maybe a wide range of applications?

I will give you my opinion right now, unless you are interested in very long range, an 8 twist is not correct. The reason is that, you will see much shorter barrel life and the VLD bullets do not kill well at extended ranges. You get runners, and that is never good. Ground squirrels, maybe, but coyotes deserve a better fate.

One of my barrels is a Shilen 1X12" and the other is a Hart 1 in 14". At the speeds you will see, there is no reason to spin a 60 bullet, in an 8 twist at that RPM when all you really need is about 180,000 for acceptable accuracy. The muzzle velocity is all I need to shoot 65 grain bullets very accurately. 70 grain VLD, not so much. I never tried 70 grain Bergers in the 12 twist because of the above concern about actually killing (bang/flop) a coyote rather than seeing him spin and run off, never to be found without dogs and a waste of good hunting time.

Therefore, if you intend to hunt with this rifle, Do yourself a favor. I suggest that you change your order to a 12 twist.

Lastly, yes, there is a possibility of vaporizing bullets at extreme RPM. I have done so with 55 grain Bergers. They were grouping very nicely at 100 yards and blowing up before 200, which I found out by shooting at a cooperating coyote out at about 200, or so. He just looked at me and I thought I must have bumped the gun? Checking it out, those bullets that were grouping so well at 100 never printed on paper, at 200.

Maybe not always, but certain bullets will not handle that RPM, and that's what it is, not speed, per se, it is the centrifugal force that causes some bullets to fly apart. Ergo, avoid a fast twist unless absolutely necessary to stabilize a really long bullet. You said you are hunting coyotes. Don't use these type of bullets. Free advice, and worth the price. BB

 

[BuzzBoss915]

Re: bullets fragmenting??

PS, if you are intending on building a machine gun, I would forget the Ackley because you really need a 26" barrel, bare minimum 24". Hardly ever see an AR with a barrel that long. You will not get the speed you expect with a 20" barrel and you will be disappointed.

Maybe you need to rethink this? There are better chambering choices in a self loader. BB

 

[utahyote]

Re: bullets fragmenting??

Great things to think about. I am building a bolt gun. Not a AR . I am building a 22-250 so I can shoot lapua brass, so why not AI it. Ring that out for all its worth. It will be a calling rig, 24" pac-nor #5 contour. Building it off a bighorn sporter action.

 

[utahyote]

Re: bullets fragmenting??

What bullet would you suggest for holding together at these speeds and not splashing on impact?

 

[BuzzBoss915]

Re: bullets fragmenting??

Well. I use the 62 Berger in my 22-243Middlested. Holds together and is accurate. I use the 65 Starke in 22-250Ackley. Holds together and is very accurate. The 62 is discontinued, but I have a supply.

I see no problem with your choice unless you intend to go with the 8 twist. Then, I have no opinion because I don't know? COULD it be a problem? Who knows?

I will tell you what a number of people I know, that have a 22-250Ackley use. The 55 Nosler Ballistic Tip. It is a well constructed bullet able to handle these velocities, BUT. Again, I do not know how well that bullet would handle the high RPM of an eight twist?

Two things. Go with a 26" barrel and forget about an 8 twist unless you want to shoot at least 75 grain loooong bullets. And those bullets make lousy coyote bullets. A 1 turn in 12" should cover any bullet you should decide on. Last suggestion: Remember this when the time comes; give serious consideration to H414 as your propellant of choice.

And, good luck. BB

edit: You can forget about surface splash as long as you stay away from squirrel bullets. 40-50 grain bullets. Use at least 52 match or preferably just about any 55 grain bullet has a slightly heavier jacket and are made specifically for coyote size animals. I have killed some very large animals with 55 grain bullets, hogs etc. Stay within that range of weights; 55/65 grain and you will never see a surface splash.

 

[RebelYell]

Re: bullets fragmenting??

First off , have you already ordered this...I kinda doubt it cause they would have told you to rethink your decision ...hopefully.

Here is a char that will kinda give you a reference to what caliber-bullet weight and twist should go by.

http://www.opticstalk.com/topic19347.html