300 win mag

[NicoyaHunt]

I have a 300 win mag and I do my reload I use 180g SST Hornady and H4831, 70g, 2900f/s, my problem is just I can not reload the brass 3 to 4 time, after that the primer pocket is enlarge and can not hold the primer, I try different primer but I have the same result, I have a friend he have a 7mm rem mag and he have the same problem, I thick is a problem witch the belt magnum.
Some body told me that I was over load the charge but I using the specification for the data books
if some body know what I am doing wrong let me know please

[elkhunter11]

All loads listed in a manual, may not be safe in all rifles. If you read the manuals, they do advise starting with the minimum load and working up, while watching for pressure signs. Those loose primer pockets after a few firings, are a pressure sign. The cases are now scrap so start again with less powder in new cases.

[Dean2]

That load is well under max published loads but the loose primer pockets are clearly telling you they are over max pressure. The exception is federal brass which will often show loose primer pockets very early and even with min book loads. There are so many potential causes for this, from bullets seated to far out or too far in to copper build up in the barrel to using 4350 when u think it is 4831 that it is near impossible to help. If you are loading your friends 7 mm too then the cause is likely related. I have 7 and 300 mag that have been loaded warm 8 or .ore times and the primer pockets are just fine. You need Eed to find a well experienced reloader in your area and have them help you out, right down to watching the full reloading cycle as u do it.

[NicoyaHunt]

I use federal brass, before I use H4350 62g now I am using H4831 70g, last week I got a new powder Hybrid 100 and I load the first 20 at 60g to see what happen

[NicoyaHunt]

Clarification I do not load my friend load, he do it by himself, I have not idea how he reload his 7mm WM, just we have the same issued with my 300 win mag and his 7mm rem mag

[skidderman]

Federal brass is garbage. Anything but federal is better. I do two loadings on federal brass with my 300 wsm then throw them away.

[NicoyaHunt]

thanks to know this, Federal brass are not really good,
this is my data in the reload

first load...good
second load ….good
third.... load I lost 10% to 30% of 100 brass
fourth... load I lost 70% of the remaining brass
so on the fifth load I have only 10 to 15 good brass, good for one more reload and after that garbage

is total different to my 308 I reloaded and reloaded and reloaded that I have not idea how many time I reloaded and steal good