Slow powder 222 load

[BCall]

I have been working with my new NOE 22-70-RN mold, shooting it in a 10" twist 222. I have not done alot of work with it, so this may not be needed, but I was thinking ( not necessarily a good thing),

I noticed Bullshop's remarks about using this boolit in a 223, and his data was for 4350 powder. I got to thinking, I have never used a powder slower than 4895 in a 222. I have followed alot of you guys loading bigger calibers at 100% density loads with the slowest powders , keeping pressures low it seems and getting respectable velocities.

Now I am not wanting to get in the upper 2000's of velocity, but would like to find something at 100% density, either not or just slightly compressed, that would give somewhere around 2000 FPS.

I cannot find any reference to doing this in 22 calibers, and was hoping someone might have tried this or had a reccomendation. I have quite a bit of RL-22 on hand, but am uncertain if this would work as I can find no verifiable data for it.

If anyone has any suggestions, please chime in. Thanks much, Billy

[Bullshop]

In my experiance a powder that is too slow to achieve top velocity potential for a cartridge can cause no harm if used at 100% density.
The reason these powders are left out of available published data is that velocities can be less than interesting to most loaders.
One of the few books that does include some such data is the one from Richard Lee.
The data I used from his book for the 223 with 4350 shows velocities in the 27/2800 fps range but at very low pressure. When I search data for potentially accurate loads I like to use data that includes pressure. I look for the powder that produces the velocity I am targeting at the lowest pressure.
Without checking a burn rate chart I am assuming that your Re22 is in the ball park with H or IMR 4831. If so what I have said will apply but being even slower than the 4350 that I used will produce even lower pressure and velocity.
If you noticed in the 22 postal match thread I did used 4831 duplexed with a kicker charge of faster powder in the 223 AI and it worked well.
One drawback is that if pressure is too low it may cause excessive smoke or soot on the cases. Black on the necks is OK but if the entire length of the case is black I would abandon the burn rate and go a bit faster or duplex that burn rate.
In short if it were me I would stuff those 222 cases as full as I could (if I am right about the burn rate) and still seat that heavy boolit to compress the powder and go with a magnum primer. See what happens!

[waksupi]

I would go with BLC_2.

[BCall]

Thanks waksupi, but I think BLC-2 is going to be a bit fast for what I want to accomplish.

Appreciate the advice Bullshop. I'm afraid that the RL-22 is close to 4831, and I am not comfortable trying duplex loads, so I'm betting it's going to be too slow. I'll give it a shot anyway, next time out.Just starting at 100% without compressing the powder. I'll have to try 4350, it's a bit faster and I have a little bit on hand here. Thanks, Billy

[BerdanIII]

From: Questions and Answers, TFS 48-3, March - April 1984

Q: I have a Rem. 700 with a 14" twist Shilen barrel in .222 Rem. I wanted to try cast in this gun and liked the looks of NEI's 71-224-GC designed by John Alexander.

Bullets cast from old linotype in this mould weigh 72 grains and are 0.792" long with gas check. I seat them to an OAL of 2.193", which is .022" short of the maximum length my chamber will allow. The bullet does not extend past the base of the case neck. I could not find loading data for a bullet this heavy in .222, so I started with 16.0 grs. of RL-7.

At 100 yards, not a single bullet hit the paper. Moving to 30 yards, only four of six hit the paper, and they were all keyholing badly. Should I have selected a lighter bullet for this 14" twist?

A: I'm not surprised your NEI 71-224-GC bullets are unstable when fired from a 14" twist barrel. This bullet is 3.55 calibers long.

According to Greenhill's rule the length of the bullet in calibers, times the twist of the barrel in calibers should equal 150 or less for stability. This method is an approximation, but gives pretty good results for cast bullets, given their typical shapes and velocities. According to Greenhill, your 14" twist barrel should handle a bullet up to about .538" long, such as the Lyman 225415. Actually, Greenhill's formula implies a substantial safety factor, and it is possible to get reasonable results with high velocity bullets, such as jacketed ones using 200 as the constant, but even doing this a 14" twist would imply a maximum bullet length of about .717", which is about the same as a Sierra 52 gr. BTHP, and your NEI bullet is a lot longer than that and would be shot at lower velocities.

John Alexander's barrel is probably a 10" twist, and that would be just barely adequate to my thinking, as the Greenhill rule for this length of bullet would imply a twist of 9.3" if the constant were 150, and 12.6" if you used the figure 200. It may be possible to stabilize this bullet in 12" twist barrels, but I would expect it to require maximum velocities in the 2000+ f.p.s. area, and at that it would be distinctly marginal.

I have this mould but haven't had time to test it out yet. I obtained a 9" twist barrel from Douglas, which I have chambered for the .223 Rem. with a long throat. I have shot this barrel with 69 gr. HPBT jacketed bullets measuring .915" long it groups consistently under ½" at 100 yds, so I have no doubt it would handle the NEI bullet at lower velocities. It also handles the 52 gr. Sierra very nearly as well. Ten 5-shot groups with the 69 gr. Sierra Matchking averaged .426", and with the 52 grain, .489". Given as well as this barrel is shooting I see no use at all for a slower twist in .22 centerfire. The 9" twist bull barrel shoots military ammunition far better than my 12" twist barrel.

I have no data for cast bullets of this weight in the .222, but I would expect you could get good results with RL-7 in the range of loads you are using, if you had a 9" or 10" twist barrel. I see no hope of getting this long a bullet to work well in a 14" twist, though in a very long, say 28" barrel with a 12" twist, you may get reasonable results if the bullet is cast very hard, or heat treated, and driven as fast as it will stand."

IMR shows charge weights, useful or not, for all the powders in their line for the cartridges in their loading manual. Reduce loads 10% to start.
.222 Remington - 55-gr. PSP
SR4759 - 15.5 - 2665 fps - 44200 cup
IMR4227 - 17.0 - 2835 - 45800
IMR4198 - 20.0 - 2990 - 42600
IMR3031 - 23.0 - 2945 - 38300 - compressed
IMR4895 - 25.0 - 3085 - 45900 - compressed
IMR4320 - 25.5 - 2985 - 43500 - compressed
IMR4350 - 24.5 - 2475 - 26800 - compressed
IMR4831 - 24.5 - 2300 - 24100 - compressed

I don't know how a bullet 15 grains heavier would affect velocity or pressure.

I tried a listed IMR4064 load in the .22 Hornet and got unburned powder in the bore and so-so accuracy, even at 50 yards.

[seppos]

According to the quick load the RL-22 would give with 100% fill (23.15 grains)about 21363 psi pressure and about that 2000 fps.. depending about the barrel lenght of course..

S

[BCall]

Thank you guys! I guess we'll see if RL-22 will work. Much appreciated, Billy