Flatning Primers and Blowing Out Primers

[Prairie Dog50]

I have a savage model 12fv chambered in .22-250 with a heavy varmit barrel. We have tried a variety of different hand-load recipes with a variety of powder and a variety of bullets in type brand and weight. All of this of course is done with the proper safety procedures; always starting with the minimum charge listed in the speer reloading manual, and the annual Hodgon's magazine reloading manual and progressively working our way up until we see signs of excessive pressure.. We can get very tight groups with this gun and these hand-loads, however in most cases we can never get past the first minimum charge without flatening or blowing out primers. Oh by the way we use CCI 200 Large Rifle Primers. We were thinking of maybe starting with the minimum charge and working our way lower in half grain increments until the primers quit flatening and when were getting acceptable group sizes. Is there any danger in this?? Or is there perhaps a better way to solve this problem??

[parkj5]

Man i got a ruger m77 thats doing the same dang thing.i have not blown any primers yet but they sure come out flat.bolt does not even get sticky.mine is a 25-06

[dmaxthad]

I have a Ruger M77 in 270win that flattens primers ever so often. Just the other day it did it with factory loaded ammo.

[J E Custom]

Originally Posted by Prairie Dog50

I have a savage model 12fv chambered in .22-250 with a heavy varmit barrel. We have tried a variety of different hand-load recipes with a variety of powder and a variety of bullets in type brand and weight. All of this of course is done with the proper safety procedures; always starting with the minimum charge listed in the speer reloading manual, and the annual Hodgon's magazine reloading manual and progressively working our way up until we see signs of excessive pressure.. We can get very tight groups with this gun and these hand-loads, however in most cases we can never get past the first minimum charge without flatening or blowing out primers. Oh by the way we use CCI 200 Large Rifle Primers. We were thinking of maybe starting with the minimum charge and working our way lower in half grain increments until the primers quit flatening and when were getting acceptable group sizes. Is there any danger in this?? Or is there perhaps a better way to solve this problem??

If you are getting pressure at the starting loads there are several reasons.

Look at the fired brass and insert a new bullet in the case, (It should fall in). If it doesent go in
easy then you have a tight neck or it is longer than the neck portion of the chamber.

If it is not to long (Can be fixed by trimming) then you may/must turn the necks down.

The other thing it could be is bullet seating depth . If it is touching the lands at all it will raise
the pressure and it will need to be seated .020 off the lands and then you can work closer to
the lands in steps of .005.

Some chambers have no free bore and this is a common condition if not dealt with.

There is nothing wrong with the primers as long as it is the one listed in the load data.

I hope this helped.

J E CUSTOM

[noone]

The length of the neck on your brass could also cause problems. If the neck is too long the chamber in your new rifle, when you chamber the round, the end of the neck gets crimped onto the bullet causing excessive, and erratic pressures.

Earlier in this thread, bullet seating depth was covered really well so I won't go into that.

Other causes could be oil or solvent in the chamber, improper headspace (even with a new rifle), short throat (covered with bullet seating depth).

I suggest making sure there isn't any oil or solvent in the chamber, a seating depth gauge, trim the case necks, and have headspace checked.

[Trickymissfit]

awhile back I ran into a similar problem with Blackhills brass. The necks were all over the place and half the primer pockets were loose after one firing! Have also heard similar results with Winchester brass (new stuff)
gary

[loaders_loft]

One other thing, if your brass has Been exposed to high pressures the primer pockets may be loose. If so then dump it and start again with new brass. Long necks may have started the problem but if you trimmed and then continued having problems then it may be loose pockets.