I have a new to me 9.3x74 in an older Heym sxs. I went to the range with several boxes of different factory ammo from 232gr, 258gr, and 285gr since I was unsure what the rifle is regulated with. All of the ammo crossed, badly (about 3" at 25yds - yeah, I know it's short distance but what I had available for a quick check of a new rifle.). I know that I need less velocity. Any way to guess how much less velocity I'm needing? I assume there are too many variables in play. I see that the Norma data has 325gr loads in the 1900s fps range. Hoping not to have to go to that heavy of a bullet. Also considered trying different powder speeds. Hoping normal weight bullet starting loads will get me there. Any thoughts would be appreciated. Thanks.

If I were in your shoes...
I'd pick the bullet style and weight you want.
Next, pick the powder you want to use.
Then, a large rifle magnum primer.

Load 4-6 rounds at a velocity you know is way too slow. It should print wide on the target.
Begin increments to increase powder and watch the target holes come together until you have an acceptable group.

If the grouping is not to your satisfaction or if the velocity is too slow for your good target, then send the rifle off to be regualted with the load you want.

If the factory ammo is not working for you, pull the bullets and use the brass and develop the load that does work for you.

Good luck. Should be an easy solution.
Cal

How old is the rifle? Heym may be able to help if it is not too old.

My Demas 470NE was made during the transition of acquisition by VC and no records are available even for 2006!

Thanks gentleman. Good advice. Not sure of the age. No import marks either. Thanks again.

quote:

Load 4-6 rounds at a velocity you know is way too slow. It should print wide on the target.Begin increments to increase powder and watch the target holes come together until you have an acceptable group.

Exactly! My .405 is regulated for Hornady factory 300 grain @ 2225 fps.
I wanted to shoot 400 grain ammo also and did just what Cal recommended and eventually have it regulating 400 grain ammo at 2050 fps!
Wunderbar!

quote:

Originally posted by Kynoch:
Thanks gentleman. Good advice. Not sure of the age. No import marks either. Thanks again.

See, Kynoch, Its easy once you ask a person who knows how double rifles work like Cal Pappas!
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