Magnum Primers

[Raptor]

I'm thinking of trying CCI Magnum primers in my 6XC. I have the first gen brass with less case cap. than either the 2nd or third generation brass.

I'm using 38grs of H-4350 with Fed 210 primers an this seems to be the max load but the gun won't shoot anything less. With the 38grs I am getting ejector marks on a few cases but if I back it down a half grain my groups open up.

My problem is I'm getting inconsistant readings on the cronograph. I can shoot a group an get a one or two foot variation between three rounds then have one jump nearly 50ft per sec faster.

The gun is also inconsistant when shooting groups. It will shoot the 38gr load into the .3s then all of a sudden I get a .6 group!!! I have weighed all the brass an neck turned it, if there is a difference in the brass I don't know what it is.

Someone suggested I use CCI magnum primers for better ignition but I know this will probably create more pressue also. Should I back my load down a grain or so when using the mag primers?? David Tubb thought maybe drilling the primer hole to .080 might help also. Anyone ever tried this??? Thanks guys!!!!!

 

[Changeling]

Raptor, maybe your rifle just doesn't like H4350!! Have you tried several different primers with the H4350?
Before you go and drill out the primer hole to 80 thousands
try some "Other" powders with various regular primers to eliminate one set of variable at a time. Write down everything pertaining to each series of shots. Save the target to associate with your write ups.
Have you had your gunsmith check out the rifle bedding and crown, this should be the first thing you do before going further, even if it is brand new? This would keep you from beating a dead horse, get my drift.
Changeling

 

[Raptor]

The other powder I tried was Varget an it didn't shoot as well as the H-4350. I tried Winchester primers an Remingtons but I had seveal of them blow during load testing with even the lighter loads so I stayed with the Federals.

I can't believe its a crown or a bedding problem when it shoots most of the groups the way it does. I have had a rifle with a bad crown an it wouldn't shoot anything well. This was built as a tactical rifle with only a 10x scope so its not going to drill one hole groups an I doubt I could do that anyway,HA).

It will shoot some groups in the .3s an low .4s then for no reason throw one or two out into the .6s. The reason I was looking at maybe it being the brass is because of the jump in velocity that I would get when shooting across the cronograph.

I don't understand why it would shoot 3 rounds at say 3044, 3046, 3042 an then 3102!!! To me there is something wrong here. Thanks for the thoughts!!!!

 

[Bullmoose]

Have you tried removing the brass that has fliers and then reload only those cases that didn't produce fliers? If it is a brass problem it should go away.

 

[Changeling]

Have you tried removing the brass that has fliers and then reload only those cases that didn't produce fliers? If it is a brass problem it should go away.

Good idea, try what bullmose said also. What kind of powder scale are you using and can you borrow another to try?


""My problem is I'm getting inconsistant readings on the cronograph. I can shoot a group an get a one or two foot variation between three rounds then have one jump nearly 50ft per sec faster.""

Can you borrow\try another cronograph?

You have to start eliminating variables to determine the problem.
Changeling