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Az Shooter
03-20-2010, 06:22 PM
I am looking for load data for a old wildcat. 22-243 Middelstead. I found it at a gunsmith deceased auction about 20 years ago. I bought it just for the large ring action but now I have a need for a fast 22 that will shoot a heavy bullet to buck high winds. The cases fireformed great with half a case of 380 and light bullets. Since then every load I have tried blowes out the primers. I have tried reduced loads for 22-250 and 220 swift as starting points with no succes with 70 gr Speer

versifier
03-20-2010, 09:14 PM
According to Handloader's Manual of Cartridge Conversions, it is basically a .22-250 with a 30 degree shoulder, case capacity 53.19grs water or 3.44CC. It is one of a bunch of similar wildcat cartridges in use before the .22-250 was accepted as a factory round. It is made most easily by simply fireforming a .22-250 in the Middlestead chamber and avoiding the extra work of necking down .243 cases and then reaming or turning the necks to correct thickness. The data listed there was from Middlestead in 1964:
72gr bullet, IMR4831 45.0gr, 3450 fps

Regular .22-250 data should be correct for it.

First I would be checking the twist of the barrel to make sure the rifle wasn't set up for lighter bullets. 1:10 and 1:12 were and are very common .224 barrel twists, but they may have difficulty stabilizing such a long bullet. Like with the .223, 1:8 or 1:9 would be optimum for heavier bullets. (Bearing in mind that barrels can't read, some will nevertheless work fine despite not being of optimum twist. I have looked like an idiot before by declaring a 1:10 wouldn't stabilize a 70gr bullet and then watched the rifle's owner shoot a series of .5MOA groups with it.)

I would be trying 4064, Varget, and RL15 with 70gr bullets as I think 380 might be a bit too slow - that may be part of the problem. Also, it is never safe to use reduced loads with a ball powder (I don't use 380 and I can't remember if it is ball, flake, or extruded).

If the cases were formed from .243's, the necks may be much too thick for the chamber and pushing pressures well into the red zone or beyond. If you are blowing primers, something is causing overpressure.

Az Shooter
03-21-2010, 11:51 PM
Tks for the info. My 243 brass is not the problem. I recast the chamber to check the neck dim. only to find no problem but I saw that I have a very long throat. That got me thinking about twist rate. Middelstead made up this cartridge to shoot heavy bullets at chucks across canyons, through the wind. I expected to find a twist rate of 7 or 8. I have a twist rate of 1 in 18. In 20 years of being a gunsmith I have never seen this rate before. Even 22 rimfire are 1 in 16 or 1 in 17. I guess I will be shooting very light bullets or getting a new barrel.

versifier
03-22-2010, 03:55 PM
1:18??!!! Wow. I have never heard of a .224 barrel with that fast a twist either and I used to make them. Sierra makes a pair of 40gr bullets, a HP and a BK. I would start with either of them and 3031, RL7, or 4895, but I don't know if they will stabilize. Just out of curiosity I might even try some 55gr cast over reduced charges of 3031 (26.5gr Cast Start). They might stabilize at the lower velocity where a jacketed bullet would not. The long throat puzzles me, unless it was an attempt to reduce chamber pressure ala Weatherby. He might have been custom swaging or casting super light bullets and built the rifle for testing them. There was a major trend towards faster and lighter in the early 60's. With that in mind, it seems to me like it was intended for hunting small varmints, not target work.

runfiverun
03-22-2010, 08:09 PM
slow twist rifles beg for cast boolits i'd definatly explore that avenue.
a 22 loverign in 60 or so grains might just be the ticket at 2700 fps from a fairly hard alloy [16-18 bhn] great for varmints,targets.
for deer i'd look elsewhere or re-bbl.
sounds like a re-chambered 22 bbl.

gemihur
12-29-2021, 03:12 PM
22-243 Middlestead loads as taken from Reloaders Nest archives
https://web.archive.org/web/20171012062146/http://reloadersnest.com/detail.asp?CaliberID=100&LoadID=1147
Load 1147 in caliber .22-243 Middlestead
LoadID 1147
Bullet Berger HP MEF
BulletWeight 30 grs
Powder Alliant Reloader 15
PowderWeight 50 grs
Primer Federal 210
Brass Make Winchester
Barrel Length (inches)
C.O.L (inches)
Velocity 5278 fps
Group 0.554 (inches by 3 shot at 100 yds)
Submitted Date 3/18/2002 1:06:00 PM
Energy 1852 ft-lbs
TKO 5.02
OGW 198 lbs
IPSC PF 158.34
more loads listed:
https://web.archive.org/web/20170830155216/http://www.reloadersnest.com/frontpage.asp?CaliberID=100