LONG RANGE CAPT Posted June 19, 2011 Report Share Posted June 19, 2011 I have a 6.5x47 Lapua and although very accurate, its popping primers on a all to regular basis. The load is as follows:- 35.5gr RL15, 123gr Lapua bullets, CCI 450 primers, seated well off the lands - (so no over pressure). The rifle groups in the .2's and the rounds are heading down range at 2915fps. I'm not getting hard extractions of any sort, but each time the primer pops a small bit of primer metal gets into the bolt, fowls the bolt and results in an inability for any further shots to be fired till the bolt is stripped and primer metal removed. Having looked at a number of variables I habe been able to rule out most but am wondering if it could be the firing pin firing to far forward ??? Any help or thoughts would be much appreciated. Kind Regards Rob Link to comment Share on other sites More sharing options...
varmartin Posted June 19, 2011 Report Share Posted June 19, 2011 Firing pin protrusion is in the region of 0040-0060 inch from memory. When the primer doesn't `pop` is it cratered badly ? ps. `Seating well off the lands ` is no guarantee that your load is not to hot. !! Link to comment Share on other sites More sharing options...
Chris-NZ Posted June 19, 2011 Report Share Posted June 19, 2011 What's the action Rob? I'm thinking of firing pin diam here Chris-NZ Link to comment Share on other sites More sharing options...
oaken Posted June 19, 2011 Report Share Posted June 19, 2011 Probably is overprotrusion, should be adjustable. check the tip of the firing pin for damage which can exacerbate the problem. Might need reprofiling to a nice round shape. Link to comment Share on other sites More sharing options...
LONG RANGE CAPT Posted June 19, 2011 Author Report Share Posted June 19, 2011 The rifle is an Accuracy International AE MK II, the firing pin is the same as used on .308 Regards Rob Link to comment Share on other sites More sharing options...
foxing2night Posted June 19, 2011 Report Share Posted June 19, 2011 The rifle is an Accuracy International AE MK II, the firing pin is the same as used on .308 Regards Rob Hi Rob, Should that read 38.5 and not 35.5????,, As you know that this is my load that i have used for a long time with no probs,,,, One thing that i have noticed is that there is a lot to lot variation with reloader 15,, this could be one factor????? start loads a tad lower and work up!!!! The other factor could be that the AI bolt, firing pin is for a 308, that means that it has a big firing pin and has a lot of protrusion and a fair bit of a gap around the pin??? This subject has been covered by an article by Zak smith(cant find the link) He reported that the Ai AW that he uses in 6.5x47 does crater the primers, but with no ill effect to his load or his shooting,, it is just a trait of the AI rifle bolt set up,,, Some people do have there bolts re bushed so that the primer does not flow back up the bolt face on firing!!!! I would think that you will have to reduce you load,,and see what happens, then work back up??? Really i would like to see your fired cases????, my back is a lot better now so we could have a outing next time you are home???, it would be nice to catch up with both you and Glen All the best, Darrel Link to comment Share on other sites More sharing options...
The Gun Pimp Posted June 19, 2011 Report Share Posted June 19, 2011 Rob, Use CCI Small Rifle magnum primers - solves the problem. Vince Link to comment Share on other sites More sharing options...
rabbit fingers Posted June 20, 2011 Report Share Posted June 20, 2011 Rob, Use CCI Small Rifle magnum primers - solves the problem. Vince Correct me if I'm wrong but cci 450 primers ARE cci small rifle magnum. aren't they? Link to comment Share on other sites More sharing options...
The Gun Pimp Posted June 20, 2011 Report Share Posted June 20, 2011 Correct me if I'm wrong but cci 450 primers ARE cci small rifle magnum. aren't they? Er...... - put it down to my age! Vince Link to comment Share on other sites More sharing options...
c18rch Posted June 20, 2011 Report Share Posted June 20, 2011 I had a bad batch of CCI 400's a while ago. Kept piercing the primers with a load that I've used without problems for 7 years or so. I bought a new batch and had no problems since so I just put it down to a bad batch. Luckily I only bought a couple of trays of that batch as opposed to my usual brick of 1000. Link to comment Share on other sites More sharing options...
Guest dasherman Posted June 20, 2011 Report Share Posted June 20, 2011 I had a AI in last year in .260AI that was popping primers regularly. The owner had had the firing pin and spring replaced and protrusion was correct. Bushing it and reducing the firing pin diameter cured it. Wanabe snipers should stick to .308. Link to comment Share on other sites More sharing options...
Chris-NZ Posted June 21, 2011 Report Share Posted June 21, 2011 That's what I was alluding to (in an excessively obscure fashion it seems..) Chris-NZ Link to comment Share on other sites More sharing options...
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