Should a 1:12 twist stabilize a 48g bullet? with pictures

I just got a free box of ammo from Lehigh Defense to try out. It's a 48 grain, brass, "controlled fracture" bullet. I'm firing it out of a 1:12 twist Remmington 700.


Here's the pictures. The good group with round holes is 55g Federal Premium Frangible ammo. The oblong holes are from the Lehigh. EDIT: The Leghigh picture should be rotated so that the holes are on the right side of the target. I don't know what it turned that way when I uploaded it.




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I was told by the company that my barrel twist may be a bit slow, but I don't know enough about that to argue. He also said that even though the bullet isn't flying straight, it will still fracture as it is intended, but I have my doubts.
According ot what I looked up online, a 1:12 or 1:14 should stabilize a bullet that small.
Any thoughts?

I have a Remington 40XB in 223 that I shoot 40gr Hornady Vmax with it and it is an absolute tack driver....it shoots .375 at 100 yards...so yes I think you should be able to stabilize 48 gr with no problem

so i would have to assume it's an issue with this new ammo then.

Brass weighs less than lead.

A 48 Gn Brass bullet bullet is much longer than a 55Gn Lead bullet.

Length, not weight is the issue.

Pull one of the bullets. I'll bet its longer than a conventional 60Gn JSP

Bingo.

A 48 grain brass bullet is gonna be a lot longer than a 55 grain jacketed slug.

does this help?



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according in iruler.net

The brass bullet is about 2.25 mm
The lead bullet is about 2.15 mm

That's the measurement I get holding the bullets up to my screen

another. they're pretty damn close. Would that .1mm matter?



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It might. You're in Alaska right? Nice and cold there?

The reason the military went from 1:14 to 1:12 twist is because 1:14 couldn't stabilise the 55gr bullets in cold weather.

You're running a faster twist than that, but also shooting a longer bullet. So it could be that it would run fine in the summer but not the winter.

Could a factor of it also be the surface area that is in more contact with the rifling?

not alaska. I just never fixed my profile. Those results were from a range day yesterday when it was about 32 out.

Yeah, length is definitely not a problem, then.

So it's saw cut like that? Are we sure those "halves" are splaying out in mid air or even breaking off?

I really have no way of knowing what it's doing. The ammo is pretty pricey, almost 2 bucks a round. The guy told me that he's positive we'd still have success using it even if it isn't flying perfectly. I don't quite believe that.

Here's a link if you're interested. Right now I'm not very impressed with them
http://lehighdefense.com/ammunition.html

What is the weight of the polymer tipped hollowpoint?

All their stuff looks pretty gimmicky.

It's a 55gr Nossler Ballistic TIp

Well my gut reaction is I wouldn't trust it for much.

Can you try it in another rifle or twist/ or Ar upper to attempt to assess it better? If you're firm with the Remington that's tossing them askew then just replace the ammo and drive on. A blitz or hornady Vmax or Ballistic tip would also come apart fast if that's the goal. All three of those are fantastic shooting bullets.

My suspicion is that gimmick bullet simply lacks concentricity/uniformity. Or they lack the QC fortitude to scrap rejects, box em and ship them.

that cut looks too deep to retain integtrity at high RPM

I appreciate all the responses guys. I can try them out of my AR that has a 1:7 twist to check, but I don't have a lot to play with. I shot about 6 at the range. That leaves me with 14. I don't think I know anyone that has a 1:14 if I wanted to try that. I wanted to be able to drop some deer with them to try them out.

I need a non lead, fragmenting bullet. This place looked promising, but now I don't know.

I'd bet money that if those bullets are all saw cut down the center like that, the halves are opening up during flight. What's the MV? I'll assume roughly 3150 fps, at 1 twist every foot (12"), that's 189,000 RPM. If jacketed bullets can be made to disintegrate in mid-air by over spinning them, it is not beyond reason that a bullet with a saw cut down the majority of the middle is going to open up some during flight.

Also consider accuracy. Case in point, I used to have a 1:12 twist M16 upper (1964 manuf.) that would group 50gr bullets about 1.5 MOA. I tried 62gr. JHP in it one time and it kept the bullets BARELY stable at 100yd. Groups were about 8-10" in diameter. By 150yd they were tumbling and key holing through the target. At 200yd they were impacting in about a 8ft diameter area.

You seem to encounter a slight loss of accuracy, but nothing near as bad as unstabilized bullets IMHO.

If you need a lead-free hunting bullet, I suggest looking into Barnes.

This is a bit off topic, but I believe the Berger guys looked into this and discovered it wasnt the spin that was the problem, it was the friction from the barrrel heating up the bullet enough to partially melt the lead core, separating it from the jacket and causing catastrophic destabilization. Shooting paper at close range revealed a mist of lead coming out of the match hollowpoint. Thickening the jacket solves the problem by providing a bigger heat sink to slow down the heat transfer to the core long enough to get the bullet out of the barrel.

If you're hunting deer with .223 then you don't want light fragmenting round anyway. Barnes TSX works great on white tail rodents around here.... Great expansion and weight retention. Solid copper.

Agreed on the barnes TSX

Well, I'm not quite "hunting". I'm shooting deer at night legally. If you want in on the story go over to the suppressor forum and look up the "deer depopulation" thread.

I was able to drop one deer with a high neck shot last night with one of these bullets. It went right down, which is good. The bad part is that everything came out the other side. I had 3 tiny holes around a large center hole. So the bullet fractured into pieces as it's supposed to, but didn't expend its energy in the deer. So I'm thinking I can't use it.

Have you looked at the Nosler lead free BT, I would think it would work for your desires.

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