Does any company currently make a 90 grain .224 bullet? I know several make 75-80 grain weights.

Also what twist do you think such a critter would have to have? 1-7 or maybe 1-6?

Thanks,
HBB

HB Bear,

At the present the only mfr that makes the 90 gr VLD is JLK in Arkansas. The only barrel maker making a fast enough twist is Pac-nor , with a 6.5 twist.
Regards, Lee M. Land

Yep, JLK is the place. In 2001 there was a mass buy put together by some highpower shooters to induce the manufacturer to make some. At the time they were not a regularly produced item. Things may have changed now that more people are getting good results with them.

Krieger is supposedly also making the 6.5 twist barrels that are needed if you are going to shoot the 90 grainers in an AR-15.


A 22BR or a 22-250 ( and 220 Howell <img src="/ubbthreads/images/graemlins/smile.gif" alt="" /> ) bolt gun can get away with slower twists.

Scott

Actually, it is fairly easy for all of the cut rifle barrel makers to provide the 6.5 or any other twist when they are using a sine bar rifling machine. The button barrel makers have to go to the expense of making a new carbide button for each twist rate and caliber.

Regards.

Two problems to look out for -- and count yourself lucky if they don't hit you:

� With the 6.5-inch twist, any velocity over 2,600 to 2,650 may spin the bullet too fast for it not to spin apart in flight. Spin rates around 300,000 rev/min are marginal -- expect bullets to spin apart in the air at spin rates around 325,000 to 350,000 rev/min (sometimes less).

� The 6.5-inch twist may over-stabilize the bullet (it may not tip nose-forward as its trajectory curves over and down, and therefore will always fly at the same angle to the horizontal as when it left the up-tilted muzzle).

To calculate the longest twist (in inches) that you can reasonably expect to stabilize any bullet adequately, try this looser form of the Greenhill equation:

twist = (200 � diameter � diameter) � length

of the bullet, in inches.

I don't know the length of the 90-grain JLK, but I doubt that it's so long that it absolutely must have a 6.5-inch twist. I'd guess that an eight-inch would do it if the barrel's any good.

Ken - That was definitely the point I wanted to make. A 6.5 twist is only wanted if you are shooting an AR-15. The folks doing well with it are getting velocities in the neighborhood of 2700 fps. Right at that 300,000 rpm you mentioned.

What is interesting is that Sierra 75s and 80s do not seem to exhibit any accuracy issues in the same rifles. The only barrels that I'm aware of that have been used were what I'd consider quality barrels.

Will a 1 in 7 twist stabilize the 90s in an AR ? Sometimes yes, sometimes no. Results varied.

Regards,
Scott

I don't know if you want a game or target bullet? About 1987 I designed a .224 Magnum to do what the 243 does and I got some 88 gr bullets from a Mr. Allread of Ogden, Utah. They shot fine in a 1-9 twist at about 3200 fps MV.

The bullet was a "partition" made by putting a smaller bullet jacket backwards into .224 jacket. This bullet was very accurate when shot at 200 yds with groups around 1.5". The bullet was a semi point.

I have not been able to contact Mr Allread of late. The barrel is worn out anyway and the reamer sit's here. The anticipation of the project was greater than the realization.

I fired a test shot for expansion into soaking wet newspaper with that bullet at about 50 yards. The bullet expanded perfecly. Just as a standard I asked an old club member to shoot into my newspaper with his 270 with the 140 Hornady's that he was shooting. The 270 made a big cavity. The .224 88 gr made a small cavity. I never hunted game with the .224 Magnum after that test. I have better guns.

Ahh yes... The heavy .22's are interesting, to be sure, but a 270 is, well... a 270! <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" />

Dan