This is, um, quite quick! Do you notice the ES diverging at these higher velocities at the edge, vs lower velocities? I noticed you mentioned different primers to help tame that? I don't reload, but I'm fascinated with the science behind it.
Mark, I have a question. I really really like Alpha Munitions OCD brass, but they don't make the .243 Win brass. The closest thing they have is the .260 Remington brass with the Large rifle primer. Do you think that would be a problem sizing them down to .224 for my 22.243 project? Or would I end up with the brass being to thick in the neck area? Of course I could always just use Lapua .243 Win brass. I like them too. :)
The 260 Remington brass is going to be a headache for you, IMHO. You are going to need a forming die to reduce the neck to .224" and you will have to turn the necks down to at least .015" thickness. I suggest using 243 Winchester brass (Lapua would be excellent). You still may need to turn the necks down somewhat, but you won't need a forming die. Also, the barrel on this rifle has a 1 in 20" twist to maximize velocity with sub 50 grain bullets. I hope this helps your decision. Thank you for watching.
@@markcarew6724 Yes Sir, it did. I'll just go with Lapua on this one with a bit of neck turning. I'm gonna go with a 1 in 8 twist or maybe a 1 in 9 twist. I only want to to drive the heavies. Like the 85.5 grains and higher bullets. Thanks! :)
@@markcarew6724 Will do. Right now I'm trying to decide what twist rate I want and what barrel length. I can't decide if I want a 1:8 or 1:9 twist rate. That will depend mostly on the velocity I will get with heavy for caliber bullets. If I can "comfortably" get high speeds at 3250+ with the 88 or 90 grainers then the 1:9 would be fine to use. The more speed you have the less twist you need, but a balance must be struck to sufficiently stabilize the bullet. I REALLY don't want to overspin them, but I don't want to underspin them either. lol.
I ran your numbers through a Berger Bullets stability spreadsheet for a 85.5 grain and 90 grain 0.224" at 3250 fps. According to the calculations, you will need a 1 in 7" twist to stabilize both bullet choices; 1 in 7.25" minimum. The chart indicates that 1 in 9" is far too slow and 1 in 8" is very marginal. Here is a thread on the Middlestead and heavy for caliber bullets. www.longrangehunting.com/threads/22-243.278417/ Or, if you have masochistic tendencies, try the 22-284 Winchester; it was my second choice for this project.
Thank you for watching and leaving a kind comment. This rifle was shooting a 40 grain bullet with a 1 in 20" twist barrel. I will try a 35 grain Hornady bullet next, and then a 30 grain Barnes bullet.
There were quite a few challenges for this build, most importantly, getting a rifling button made for a 1 in 20" twist. Then Hart Barrels did not want to rifle the barrel for me due to liability concerns. Eventually, Hart agreed after I signed a waiver. Thank you for watching, and save your 243 brass.
Thank you for watching and leaving a thoughtful comment. I had this rifle custom built for maximum possible velocity. It has a 1 in 20 inch twist, which makes it impossible to stabilize bullets heavier than 50 grains. I had this rifle built to test whether 5000 fps was attainable. The original idea came from Paul Middlestead during the early 1960s; he was using 75 and 80 grain bullets for long range target shooting.
@@markcarew6724 Wow that is a low twist rate. Having something like a 1 in 8 or 9 would be just about ideal for pushing heavy for caliber projectiles at high speeds, even with a shorter barrel they would still be crazy fast. I'm thinking about building a 22-243AI in my next rifle, but it will be to push heavy bullets.
A 22-243 AI sounds like an interesting project. Back in the early 1960s, a gentleman by the name of Clarke built the 224 Clarke by necking the 7x57 to 22 caliber. He used a fast twist barrel to fire his own 90 grain bullets. It might be faster than the project you are considering currently . . .
I believe Clarke experimented with the 30-06 necked to 22 caliber before settling on the 7x57 Mauser case. He found the larger 30 caliber case provided very little velocity gain with severe throat erosion. Although Clarke didn't have access to all the great powders we have now.
Thank you, Ghost Rider. This is effectively the top velocity I can achieve to this point. I may be able to fine tune the loads with a Federal 215 primer, at least from an extreme spread view. Primer pockets are still tight, but bolt lift and extraction are quite hard. Thank you for watching.
Your 22 CHeetah is probably similar with very light bullets. This rifle was chambered with a 1 in 20 twist barrel to help with velocity using light bullets. Does your CHeetah use cases with the small rifle primer or large rifle? Thank you for watching and leaving a comment.
@@markcarew6724 good question it wasn't mine but am older gentlemen that I ran into while I was out shooting. I know it used a .308 "remington bench rest case* which is unobtainium now days. I have a 17 mach v that I need to work up loads for.
@jacktrout5807 The 308 Remington Benchrest cases used a small rifle primer. These cases were used by Fred Huntington and Jim Carmichael to create the 22 CHeetah. Hence, the capitalized letters in the cartridge name.
I use to have a 220 swift. That got 5065fps with a 40grn Hornady Vmax. With a stout load of Winchester 760.. 14 twist 27" barrel. Needless to say,..barrel smoked at 1800 rounds.. It sure was fun though
Thank you for watching. These loads are right at the top of safe pressure. The primer pockets are still tight, but bolt lift and extraction are quite hard at this point. The groups are good, even excellent, around 3/8ths to 1/2 inch for five shots. I would like to try Magnum primers to reduce the extreme velocity spreads. I would also like to try 30 grain Barnes bullets next, but I don't know how I will chronograph the results. I can't take credit for this cartridge, it was developed by Paul Middlestead in the 1960s. I merely slowed the rifling twist dramatically to reduce drag on the bullet while in the barrel.
