Rem 700P light primer strikes

[Catalyst81]

I shot my Rem 700P in .308 for the first time. 6 out of the 25 rounds were duds (failed to fire). I think it may be due to light primer strikes. Never had this issue before and I could use some help trouble shooting. The rifle: stock except for a muzzle brake installed by Randall, bolt tuning by Randall, and Timney trigger installed by myself. I was also using rounds loaded by myself for the first time (new Winchester brass, CCI LR primers, IMR 4064). I loaded them for magazine length. The issue presented itself when the rounds were loaded through the magazine and when loaded one round at a time by me. I've included pics below of fired rounds and the dud rounds. Any suggestions on troubleshooting?

Duds







Fired rounds

[MongooseV8]

Certainly looks like light strikes. Either dirt in your bolt preventing the firing pin from moving all the way forward, or those primers are seated too deep in the primer pocket. Kind of hard to tell from your pictures, but I would clean out the bolt body.

[thegamettt]

My friend just had this issue, he swapped out the firing pin spring and it fixed the problem. Disassemble and inspect the bolt.

Are you priming on the press or with hand primer?

[Yerman]

Sorry to thread jack but as a side note, would you consider the fired primers to be "cratered" and a sign of overpressure? I'm still learning about the signs of overpressure and I thought that is what you do not want to see

[buffybuster]

Possible causes:
-Excessive Headspace
-Weak striker spring
-Timney trigger. (some Timney triggers do not retract the cocking piece far enough back)

Install the OEM trigger; if that fixes your problem, then you know where the issue is.

[btm]

Could be primer not seated?

[Catalyst81]

My friend just had this issue, he swapped out the firing pin spring and it fixed the problem. Disassemble and inspect the bolt.

Are you priming on the press or with hand primer?

Primed with a RCBS hand primer.

[Bushwack44]

Had the same problem in a Mossberg.

I disassembled the bolt, let everything soak in Ballistol for a couple hours, cleaned, re-assembled....and life is good.

I shot my Rem 700P in .308 for the first time. 6 out of the 25 rounds were duds (failed to fire). I think it may be due to light primer strikes. Never had this issue before and I could use some help trouble shooting. The rifle: stock except for a muzzle brake installed by Randall, bolt tuning by Randall, and Timney trigger installed by myself. I was also using rounds loaded by myself for the first time (new Winchester brass, CCI LR primers, IMR 4064). I loaded them for magazine length. The issue presented itself when the rounds were loaded through the magazine and when loaded one round at a time by me. I've included pics below of fired rounds and the dud rounds. Any suggestions on troubleshooting?

Duds

[ar15barrels]

Possible causes:
-Excessive Headspace
-Weak striker spring
-Timney trigger. (some Timney triggers do not retract the cocking piece far enough back)

Install the OEM trigger; if that fixes your problem, then you know where the issue is.

Timney triggers definitely don't pull the striker as far back.
I can see that when I do my bolt tuning as I am reducing the striker travel to make the bolt close smoothly without the bolt body drawing the striker back to be able to close.
Timney triggers don't need as much modification to the cocking piece as stock triggers do.
This is why I don't do bolt tuning with stock triggers!

Where I see the most problems with timney triggers is with oversized bolts.
Timney has such tight tolerances between the sear and the bolt body diameter that when you go from a stock 0.695" remington bolt to a 0.700" or 0.703" bolt body, the bolt body will drag on the sear.
I grind a little radius in the middle of the sear and the problem is solved.

I'm going with excessive headspace from the new brass combined with lightle seated primers and shortened striker travel as the cause.
An extra power spring will probably fix it right up.

[Catalyst81]

Thanks for all the suggestions. I just neck sized the new brass for the first firing, so headspace could be part of the issue. I'm going to pick up an extra power spring and full length size the brass and see how it does.

[diver160651]

Rem 700P light primer strikes

Could be primer not seated?

I'd agree.. your best course of action would be to put the unfired rounds with the "light" primer strike back in and try to shoot them again. If they go, then it was a slightly unseated primer.

The FP hits and it moves until it finishes seating, but the impact is often softened enough that it will not fire. But because of this, it is hard to tell as it looks like a light strike.

If they don't go on the second attempt, then look at your other gear.

[LynnJr]

Possible causes:
-Excessive Headspace
-Weak striker spring
-Timney trigger. (some Timney triggers do not retract the cocking piece far enough back)

Install the OEM trigger; if that fixes your problem, then you know where the issue is.

This pretty much covers it. If you think that the bolt or firing pin are dragging internally buy a small bottle of Rosignol lighter fluid and squirt it down the firing pin hole then shake the bolt to get rid of the fluid.
Works great on triggers so throw the unused portion in your range box.

[bellwilliam]

I had the same issue with my K31. Not sure if it is unique to K31. But it was because rounds were loaded too long (COL) in my case. Apparently a common k31 issue.

[pacrat]

I'm going to pick up an extra power spring and full length size the brass and see how it does.

FL sizing will exacerbate the issue by moving the shoulder back.

When doing dianostics. ONLY change one thing at a time. That isolates the issue that needs attention.

JM2c

[LynnJr]

I am in agreement with PacRat no need to full length resize the brass.

Could you do a test?
Take a single layer/piece of cellophane tape and place it over the base of a case that didn't fire.
Using a sharp knife trim off any excess tape.
Insert the round in your gun and tell us how the bolt closes.
If it closes easily add a second layer/piece of tape and repeat the test.
Post your results.