Having problems with 11VT in .223, firing pin going through primers..

[gotcha]

Great pics BillPa, proving there's more than one way to skin a cat :) Exracer claims his F/P is non-adjustable type & has about .055" protrusion. Perhaps his simply re-tapering the F/P tip would be an improvement. You've inspired me to take another look at my Mod. 12 bolt. I like saving money with DIY :) Now we need to hear from Exracer Hint Hint

[Exracer]

I measured the pin and the pin hole clearance..I have a diff of .0025 surely not much free play going on there..The AXIS non adj pin is in it so I shimmed it where it bottoms on bolt surface inside when it goes forward..I made a shim of .013 so now I have a protrusion of .042..Looks like might be too much yet? I do like the pin point change BillPa has done on his..Did you spin it in a lathe? I am a doit myself person...Thanks guys for all the help..Exracer

[BillPa]

Did you spin it in a lathe?

No, a belt sander w/120 belt by rotating it while moving it in an arc.

Bill

[Exracer]

Thanks BillPa, I'm going to try do it to mine...I hope to try my shorter version tomorrow or late next week and then retaper it..Exracer

[gotcha]

EXRACER........... PLEASE let us know how it all works out so more followers can benefit.

[bradsc]

My Model 12 BVSS did the same thing. 1. I found that 25gr of Benchmark was right on the edge for 55's. I tried a few loads and decided to stop using Benchmark. Just using Varget now. 69SMK, 25 gr Varget, 2.30 COAL, M205GM primer has done the best. 2. CCI 400 just did not do a good job for me. I had several duds on just about every trip to the range. I have switched to Federal M205GM and have not had any issues. The primer change did change the rifle zero about a 1/4 moa. The 205GM shot lower than the 400's.
Just a few other comments on .223: I am seeing my groups really open up at 200 yards and are about the same or sometimes smaller at 300 yards. The bench guys say the 69SMK does not stabilize until 300 yards. My .223 seems to be sensitive to a dirty barrel. If I clean after every range trip the groups are better than if I clean every few trips.

Good luck with your primer development.

[Exracer]

Bradsc, I have had 25.7 benchmark with Lapua match brass that worked fine with CCi 400's..The ones (CCI400)that went through I checked were PMC on the 4th reload but still had tite primers....Also had some Rem 7 1/2s go through..Only dud primer I have had was a Rem 7 1/2..I clean after every trip to range and I shoot about 25 to 40 rnds per trip..It shoots small groups during that time...Some say to stick to one powder for the day but I have had good results with both Benchmark and Varget..My smallest groups are with 69mks, 26 gr Varget, 7 1/2 pri, Lapua brass all 1.750 and fire formed and neck sized only, and .020 off the lands..Groups are 1" to 1 1/16" at 300yds with good scope...Thanks for your help..Exracer

[Exracer]

I have not been to the range yet to try my spacer/firing pin setup..It measured .042 protrusion from bolt face..I thought that was too much yet so I added another spacer and now have .033 protrusion..My friend that shoots with me has some Remington rifles (XR100)and he says his will make a .025 dent in the primer..I loaded 3 empty brass with just CCI400 primers and it fired them perfect..This was without powder making pressure against the cup from inside..We will try it later this week and see if it's happy..Exracer

[Savage Sniper]

I am new to the forum and have been having the issues with cratering and popped primers. I head space off the lands at .020 and use 25gr Varget with 6.5 rem primers The projectile is a 60gr Vmax and 69gr Nosler Custom Competition. Had the rifle for years and never had the issue before. I am thinking with what I read and seen with the awesome pics that I have the same problem. My question is do I need to regrind the pin or purchase new? I forgot to mention that it is a Model 12 Bull Barrel .223 rem.

[sharpshooter]

You need to change primers. 6-1/2 Remington primers are for small cases like the 22 hornet. A 7-1/2 would be better.

[LHitchcox]

Have you shot factory ammo in it. I would do that to set a baseline. If it did not pierce factory primers, then you either are creating headspace issues by oversizing the cases or you need a primer with a thicker cup. If factory ammo does the same, then you have an issue.

[MS50]

I had trouble with my load blowing holes in the primers, CCI 400s. The loads were fired in my Mod12 FCV .223. I was using 24.4 gr of H335 in Rem brass and 69SMK bullets at 3062fps. They were seated .010 off the lands. Their performance was great, but I could feel a spray on my trigger hand, and the primers were pin holed. I can only assume it was the increased temperature on that day. I dropped back to 23.0 gr of H335 and found a node at 2765fps. They shoot well, and don't go transonic until about 750 yds per my ballistic program. I figure that's good enough. Several of us examined my bolt face, and saw no damage or abnormalities on visual inspection. Firing pin problems is an interesting concept. I'll follow this thread to see what comes up.

[Newbe]

Actually I haven't found the fit between the pin hole to be too large, but the profile of the pin tip itself allowing a gap between the hole when it strikes a primer. Two pins...
http://i47.tinypic.com/3096838.jpg

The one on the left is original on a taper, on the right one I re-contoured to a radius. IIRC the taper from the tip to the shank extended back ~.030". The one on the right about .010".

The same two pins set to .020" protrusion or about the maximum a pin will indent a primer cup.
http://i50.tinypic.com/2ur0aaw.jpg http://i48.tinypic.com/2e3oq5s.jpg

The factory taper on the factory pin on the left allows a gap for the primer cup to flow into resulting in cratered and or blanked primers whereas the one on the right is still it's full diameter in the pin hole @ .020" with .010" to spare.

Bill
I know this I an old thread, but it's relevant to my current issue (lots of primer flash, and occasional blanked primers even at midrange loads). I performed the above modification, and it did help though my firing pin is pretty flat on the end.

I still have some flash, but it seems less than before I modified the firing pin. Not sure if I should go further or not. The primers still light off, but instead of a round dimple, it leaves more of a flat spot in the middle of the primer.

Accuracy was not diminished with this modification.

Thoughts?

[Texas10]

If you're talking about a new FV, Newbe, your issue may be firing pin to bolt head fit. If you have a good micrometer, measure the pin near the tip and be sure it's at least .069 and closer to .070. My son's new FV had a real cratering/blanking problem right out of the box, the firing pin measured .0674 and producing a .0075 clearance with the bolt head. WAAAAAY too much. I ordered new pins and hand selected one to get a much tighter fit. Now it has about .003 clearance, and no more primer issues.

[Newbe]

If you're talking about a new FV, Newbe, your issue may be firing pin to bolt head fit. If you have a good micrometer, measure the pin near the tip and be sure it's at least .069 and closer to .070. My son's new FV had a real cratering/blanking problem right out of the box, the firing pin measured .0674 and producing a .0075 clearance with the bolt head. WAAAAAY too much. I ordered new pins and hand selected one to get a much tighter fit. Now it has about .003 clearance, and no more primer issues.

The pin is .068" and the hole is .072"+

So .004"+ clearance.

[Texas10]

Too much clearance, IMOP, especially if you weren't able to pin gauge your bolt head, and it might be larger than .072.

I have several spares. PM me if you'd like one.

[Newbe]

Too much clearance, IMOP, especially if you weren't able to pin gauge your bolt head, and it might be larger than .072.

I have several spares. PM me if you'd like one.
Spares?

The pin mic'd at just over .068" by a couple tenths. The hole is indeed .072"+ as I have pin gauges and the .072" goes in with some slop. The .073" will not go, so if I had to guess, I'd say approx .0725" or so for the hole. Maybe slightly larger.

[Texas10]

When I had the blanking issue with the new FV a year ago, I sent the gun back to Savage for work. But after test firing using magnum primers and seeing no issues, they did not address the firing pin issue so the nice lady in customer service very graciously offered to send me a new firing pin, gratis, but they were not equipped to "hand pick" one for good fit. So I signed a liability release, and purchased 6 more for two bucks each, hoping to get at least one that measured close to or a bit over .070. Most measured .0692 to .0698, and one in the .068 range. All were out of round by 3 to 5 tenths. So yes, I have several spares.

[Newbe]

When I had the blanking issue with the new FV a year ago, I sent the gun back to Savage for work. But after test firing using magnum primers and seeing no issues, they did not address the firing pin issue so the nice lady in customer service very graciously offered to send me a new firing pin, gratis, but they were not equipped to "hand pick" one for good fit. So I signed a liability release, and purchased 6 more for two bucks each, hoping to get at least one that measured close to or a bit over .070. Most measured .0692 to .0698, and one in the .068 range. All were out of round by 3 to 5 tenths. So yes, I have several spares.

If you have one close to the hole size, or at least closer than mine, I'd be more than happy to pay you for it including shipping.

I'm surprised they were that cheap. Mine seems a lot more complicated than to be had for that cheap. Perhaps I'm overlooking something obvious?

[FiveInADime]

Just to throw my $0.02 on here. But I have cratered primers with 25gr of Varget over a a 68gr Hornady HPBT.

This is an 11 Trophy Predator Hunter XP. That was in HOT 100° or more weather. The powder was compressed quite a bit (no drop tube).

I figured that was running WARM. Back off .2gr and no more craters.



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