View Full Version : Ruger M77 MkII .243 RSI,how much velocity loss withan 18 inch barrel?

Sea Buck
July 16, 2011, 02:06 PM
I am taking my Ruger M77 RSI in .243 out of the safe this fall for deer. I have not used it except at the range with some varmint loads. I will work up some deer loads with 95 or 100 gr bullets. If I go with a near full house load how much velocity loss can I expcet with this short barrel. And, will I get a complete burn of powder in the barrel?

July 16, 2011, 03:13 PM
From about 22 inches as the norm, muzzle velocity would decrease no more than 25 fps less per inch. I have been reloading the .243 winchester for almost 35 years & with a barrel that length, i would advise the following load:

Bullet: 95 to 100 grain nosler bt / hornady sst
primer: Wlr
powder: Imr-4895 / accurate arms equivalent (consult your reloading book for the charge weight) if barrel was a 22 inch from a bolt action, i could easily advise 40.0 grains of imr / aa 4350. However the 4895 will burn better in the shorter barrel.


July 16, 2011, 03:49 PM
You could alway switch to the new Hornady Superformance ammo. They claim less loss per inch with that stuff than with normal ammo.

Art Eatman
July 16, 2011, 05:30 PM
My Sako .243 is 19". It's worked okay on a couple of dozen bucks, so far. :)

I don't guess I've had to shoot beyond 150 to 200 yards. I use the Sierra 85-grain HPBT and generally limit myself to neck shots or cross-body heart shots. No angling shots or shots on running deer.