I am building a 500 A Square. I will be using a MRC PH action and an approximately 20" Krieger barrel.

What kind of velocity should I expect? Most of the data I have found is with longer barrels.

I know every caliber can be different; in what to expect in velocity loss/versus barrel length.

Anyone out there that has played with a short barreled A Square that would like to share their experiences/loads?

Thanks in advance

Shane

Never played with one but bet you wouldn't see more than 100fps between a 24 and 20" barrel. What you hit with it will never know the difference.

Id expect 25fps/inch loss. still a hammer. -Rob

I have tested a number of big bores but not the 500 A Square, but most big bores don't lose more than 20 FPS per inch from 24 to 20, but a tad more when you get to 18 inches...Not enough to make any difference in killing power for sure as big 50s don't use velocity to kill, they use cross section of bullet and bullet weight..Your good to go I assure you.

BTW most big bores are loaded below their capability to quite some degree in many cases so you can do some load testing and get what you lose with the short tube back without going to max in most cases or at least I have in calibers like the 404 Jefferys..

I made up for my 404 Jefferys 20 inch barrel by simply going to H4831 and IMR-4831 and kept the pressure to a real minimum and actually picked up an extra 50 plus FPS..Not many load books give data for the 404 Jefferys with the 4831s and its the only powder I would ever use for it and I tried them all.

Oh. Try h335 / Tac ray. I have used from 22h-550 magnum. THE powder for the accrels

npd345,

I'm curious, (a bit off topic question coming) if you intend for this
rifle to be hunted outside the USA? Why not use one of the .499"
diameter bullets and avoid all the politics of "50 caliber" ammo and
rifles? Certainly no elephant would know your bullet was 11/1000"
smaller diameter...

Thank you all for your words of wisdom they are very much appreciated!

DR

the gun will probably never go to Africa. If I have need of a DG rifle for Africa I am also building a 470 AccRel and have a 375 H&H.

The primary use for this gun, and the other two for that matter, is ground squirrels or as we call them around here in Idaho "Whistle Pigs"

Ferocious little bastards, and cannibals as well!

I sold one of my my old whistle pig guns, a 378 Weatherby Magnum and this 500 will take its place.

I can not think of anything much more fun than having a whistle pig standing on the edge of his mound; staring you down and ready to charge! You aim about 6 inches below him and the bullet will dig a channel, kill him and bury him all in one deadly step! If they hide behind a rock it really does not matter; just slip in a solid.

When my African PH came to stay with me I took him on a whistle pig hunt and he had a blast.

In one moment he would be complaining about the recoil of the 378 and in the next moment he would be grabbing the gun back from me to shoot another vicious whistle pig.

I will not own a gun I do not use on a regular basis and big bore squirrel hunting is the way to fill the gap.

You Idaho boys know what I am talking about.

I take the grand kids out and they use the 22's and the 17HMR, the wife the 223 and me the big bore.

So your the guy thats making those greasy spots on our rocks down in the Snake River canyon?? I hear you shoot now and then, You been giving me the shakes and shudders as I cow down behind the nearest rock!

Have not made it your part of the state for any TDG (Tiny dangerous game) hunting.

I am mostly in the Sand Hollow area between Caldwell and the Oregon border.

I am always careful about ricochets, these big bullets don't skip off rocks they go thru them!

If all you're shooting is varmints, you'll need a 26 inch bull barrel. Twenty inch barrels are suitable for use by cavalry only.

quote:

npd345: The primary use for this gun, and the other two for that matter, is ground squirrels or as we call them around here in Idaho "Whistle Pigs".

Around here, they are mainly used against charging water jugs.

quote:

Originally posted by ramrod340:
Never played with one but bet you wouldn't see more than 100fps between a 24 and 20" barrel. What you hit with it will never know the difference.

+1 to this....Ramrod is a real savvy shooter.

I have tested 23" and 27" 500A2 rifles with the same load, and same McGowen 1:10" twist,
and indeed the velocity change for 4" of barrel shortening was about 100 fps loss.
Likely holds true in going from 24" to 20" also, as others say,
only 100 fps loss.
Below 20" length you might lose more velocity per inch of shortening.
If you are man enough to shoot a 500A2, surely you can handle a rifle so chambered with a 20" or longer barrel.

Jeffe, +1 on Tac powder for big bores

In most of the really big bores I have shot and that is many from the 458 Lott to the 505 gibbs IMP and 577 N.E. I always felt like losing a 100 or so FPS was one of Gods hidden blessings!

I am in the process of getting acquainted with my new 500 AR. My second hand rifle has a 22 inch barrel. Even with H322 102 gr, the muzzle blast is deafening. Guaranteed to deafen trackers and unprotected PH's. Recoil similar to a hot loaded 458 Lott, but definitely tolerable.

So when I build my ideal 500 ar, Iam thinking of qa 25 inch barrel
Ideas?

I've got a 24" barrel on my 500 Jeffery it's about perfect for me, don't think I would ever go much shorter than 22". To each his own though.

Mine wears a 20" barrel 102 gr of Varget behind the 570gr woodleigh gives 2240 fps I doubt you would lose more than 15-25 fps. I'm happy with my 20" barrel.