Primer Pocket Tightening

juanvaldez

juanvaldez

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Anyone ever try the hart primer pocket tool or the rcbs mil crimp swager? I made a die that swages the base and rim, tightened up the pocket by at least 2 thous as measured with pin gauges. Wondering how well the commercial kits work. Its very tight to push through to get that much in a single pass, may need to make a second die and do 2 passes. Probably should just chuck em lol but wanted to see if it can be easily done.
 
I've never really looked into this much, but I somewhat assume by the time your primer pockets are loose there are other reasons to replace the brass....

That being said, I've got 12 reloads on (200) Lapua brass, only neck sizing, and I'm starting to have issues with primer pockets. Being that they weren't full resized maybe the bases are still thick and structurally sound? Brass has only been trimmed once because they remained within limits.
 
A friend has/had the Hart one. IIRC he said it isn't very consistent and he was thinking about modifying it to be used in a Dillon swager. The RCBS is for removing military crimps and makes the primer pocket looser, not tighter.

If I understand this correctly, you're basically just pushing the case through a bushing, similar to what is done in a pistol de-bulging die?
 
A friend in the US told me that when the primer pockets start to get loose he switches over to Wolf primers. They are about .0005" bigger and will get you another 4-5 loadings out of your brass.
 
An RCBS primer pocket swager is for removing the crimp on milsurp brass. It you don't have milsurp brass you don't need it.
 
All the Heart tool does is crimp the mouth of the primer pocket, and if you Google the topic you will see it does not work very well if at all. If your primer pockets are stretched and larger diameter primers don't fix the problem then its time to toss the cases in the scrap brass bucket.

It is not worth having high pressure gas leakage scoring your bolt face trying to save stretched brass.

The cases below are primarily factory loaded Federal .223/5.56 cases with oversized primer pockets after the first firing and NEVER reloaded.

193natorejects001_zps87560a0a.jpg


The exaggerated example below shows how the entire unsupported base of the case expands from over pressure. If you want your brass to last longer then reduce your load if possible or switch brands of brass looking for harder brass in the base.

flow_zps2b838d87.gif
 
bigedp51 said:
The exaggerated example below shows how the entire unsupported base of the case expands from over pressure. If you want your brass to last longer then reduce your load if possible or switch brands of brass looking for harder brass in the base.
Click to expand...

Swaging (/ˈsweɪdʒ/, pronunciation note below) is a forging process in which the dimensions of an item are altered using dies into which the item is forced.

I understand how the hart tool works and how cases expand. I dont want a hart tool, was just wondering how much they tighten a primer pocket up. I swaged the area at the base using a die. I forced a piece through a die I made so the exaggerated bulge as shown in your picture was forced in result in a 2- 3 thous reduction in the diameter of the pocket. Possibly a waste of time but the brass seems usable now. I found 4 pieces that showed pressure signs after one loading and had resulting loose pockets.

The resulting swaged brass has a primer pocket less then 1 thous bigger then an unfired piece, both will fit a .207 - pin gauge with the pin tighter in the unfired piece, neither will fit a .208 - pin


 
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I think McPherson (?) wrote up a very nice article in Varmint Hunter mag on this subject about 2 years ago. He was successful using a push through die he made himself and I'd think anyone with a lathe could duplicate what he made. Best of luck.
 
juanvaldez said:
Anyone ever try the hart primer pocket tool or the rcbs mil crimp swager? I made a die that swages the base and rim, tightened up the pocket by at least 2 thous as measured with pin gauges. Wondering how well the commercial kits work. Its very tight to push through to get that much in a single pass, may need to make a second die and do 2 passes. Probably should just chuck em lol but wanted to see if it can be easily done.
Click to expand...

Your method is much better. Hart system involves sandwiching the brass between an anvil and rod and pounding with a 5 pound hammer to kick up a burr and distort the pocket to hold a primer. If you could make your die hard enough (not to scratch) and maybe coat it with TiN, that could save a lot of brass. What do you use to push the case through? I need one for a 7/270 WSM that I fired enthusiastically in a slightly oversized chamber.

NormB
 
I use a part from a lee bullet sizer, works perfect and is a few thous under the rim size of my case. I shortened and reamed out a lee .243 die to make the sizer. It is quite hard
 
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