A few months ago I bought a Merkel SXS in 8x57 JRS. It is regulated from the factory with Norma Alaskan 196 gn SP ammo.

When I reload is it a matter of loading the Norma 196 gn Alaskan bullet to the factory velocity, or will the powder burn rate effect the regulation ?

Things that make you go hummm............JJ

It is not as simple as just matching the velocity with the same bullet type and weight as from the regulation load.

You also need same powder charge weight for same velocity with that same bullet, so as not to affect the recoil generated.

If you change one thing of the three:
bullet
powder charge weight
velocity:

Then you are back to scratch for finding the regulation point with your load.

Get that factory recipe right or work up from scratch with whatever you want.

ONly shooting for group will tell you that..

Start by shooting a few groups with the right barrel, then shoot a few groups with the left barrel...The barrel that shoots the WORST is the best group you can expect from your rifle, so you now know what your goal is for accuracy.

Then you must change your sight setting to zero at 50 to 70 yards..

Now the business of finding a load begins..shoot two and see where they land..If the group is wider than your previous WORST group then you will need to increase the powder by a grain, if the shots cross on the target then you decrease the powder charge by a grain. do this until you get a 4 shot right, left, right left group the size of the original WORST group you fired in the beginning...

That is how its done....not as complicated as it sounds..I load up ammo starting low and then with increased grains by one grain at a time. and can usually do it in one sitting as a rule.

Then use the left over or unneeded ammo to shoot dirt clods etc. off hand at the range.

quote:

Originally posted by JJ_Miller:
A few months ago I bought a Merkel SXS in 8x57 JRS. It is regulated from the factory with Norma Alaskan 196 gn SP ammo.

When I reload is it a matter of loading the Norma 196 gn Alaskan bullet to the factory velocity, or will the powder burn rate effect the regulation ?

Things that make you go hummm............JJ

In my experience both powder burn rate and the weight of the powder charge can affect POI of the barrels with respect to one another.

Using different powders I have been able to find more than one "regulating load" for a given bullet weight, some at very different velocities, and also good shooting loads for different bullet weights.

Don't over look the 75% rule, which seems to work well most of the time. When you find a load that shoots to regulation, use a bullet 75% of the weight of that bullet over the same powder charge. You should be close to a good load right there and only need to adjust up or down a bit. For example, for a rifle that regulates with a 500gr bullet with xxx grains of yyy powder, a 350gr bullet should shoot close to perfect and the charge should need only minor adjustment.

JPK

Thanks guys,

This is going to be a facinating journey. I'll give'er a try....................JJ

JJ, when you do work up some loads be sure and use a chronograph when shooting. All else is guess work!