300 rum doing something new.........

[Harry Knutz]

Generous firing pin hole in bolt face? They don't look too bad to me still bevel showing on outside of primer.

This, The firing pin hole needs to be bushed and the pin diameter turned down to match. I bush all of mine on new rifles I build, But I have one I have shot hundreds of rounds out of that has primers that look just like yours, It's not a problem until it pierces the primers, Then those primer blanks will get inside of your bolt and at a bare minimum will cause the firing pin to get stuck, And could cause spring or firing pin breakage. At this point I wouldn't worry about it.

Those primer pics are not a sign of a hot load, The primers aren't flattened, It is just primer material flowing into an oversized hole.

 

[Harry Knutz]

Think of it like when you pour powder back into the container, If you use a funnel with too small of a hole, It doesn't go through the hole too well, If you use one with a larger hole it flows right through, Same thing. Less surface area for the thin cup material to hold itself against.

 

[Dean2]

Ok so here is the deal, same rifle same loads and now the primers seem.to be cratering??? the only thing that has changed is this is a new brick of cci large rifle magnum primers. same brass, same bullets, same powder. they shoot the same but want to see what you may think of why this is now happening. could it just be because its a new batch of primers? the rounds were loaded and finished off the previous brick so time to reload and i opened a new brick. remington nickle brass on 2nd reload, norma brass on first reload.

So assuming you are correct and there was zero cratering on the previous batch of primers, something as simple as a slightly softer metal in the cup on this batch could be causing the issue. There is so little cratering I would not be worrying about bushing the pin hole, nor would I worry about pressure. Velocity, ES and SD stayed the same, there are no ejector marks on the base and bolt is not sticky. Good to go in my books.

 

[Harry Knutz]

Firing pin holes wear over time, They get dirt inside the bolt, Powder residue, Priming compound all sorts of debris, And it's just like having lapping compound in there, If you are the type that likes to run stuff hard and you only get a few firings before the primer pockets fail, Then you have had gases escape through the firing pin hole which cause erosion of the hole and the area around the primer. Remington holes are too big to start with, Most of you guy's don't disassemble the bolts to clean them, And over time the hole gets larger. People also tend to lose track of how many rounds have actually been shot through the rifle. I'm just saying, I know from experience exactly what is causing this issue.

 

[Calvin45]

Did your velocity stay the same?

If it did... then you're just dealing with lot to lot variance. Apparently that lot has softer cups.

If you picked up velocity (which is very possible) then you're running into pressure issues and need to redo load work.


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This. If nothings changed on the chronograph don't worry about it!

 

[silverbullet777]

Yr firing pin hole needs bushing

 

[wonderman4]

In all my years of shooting and reloading, what you are seeing is normal. You do not have anything unusual with those cartridges.

 

[Dean2]

Firing pin holes wear over time, They get dirt inside the bolt, Powder residue, Priming compound all sorts of debris, And it's just like having lapping compound in there, If you are the type that likes to run stuff hard and you only get a few firings before the primer pockets fail, Then you have had gases escape through the firing pin hole which cause erosion of the hole and the area around the primer. Remington holes are too big to start with, Most of you guy's don't disassemble the bolts to clean them, And over time the hole gets larger. People also tend to lose track of how many rounds have actually been shot through the rifle. I'm just saying, I know from experience exactly what is causing this issue.

There are 200 rounds on this bolt. The firing pin hole did NOT get bigger and the OP posted that it was not cratering his previous batch of primers. Something changed but it wasnt the firing pin hole. We need to carefully asses the variables and issues actually in play and spend enough time reading the actual info provided to give quality advice. We need to deal with the actual issues, not all the extraneous what ifs that are possible.

 

[Harry Knutz]

The firing pin hole is too big period. That's what causes this primer problem. The pic of this firing pin shows the lower pin hole has been made oblong from wear, It's from debris in this case, But in many case it can be gases, The upper one is borderline. Remington firing pin holes are already close to being a problem when they left the factory. I'm not saying the OP's is worn like this photo, But if you know anything about AR-10, LR308 bolts, You know that they have factory holes that are too big when they are new, You put a High pressure round like .260 Remington or a 6.5 creedmoor and now you are blanking primers, But what do I know? I've only been working on this stuff for a long time.

But like I said earlier, I wouldn't worry about it until it Pierces/Blanks Primers.

 

[JAYgs8163]

Flowback can be common around the firing pin hole. If everything else is working as it should and it bothers you then have the firing pin hole bushed.

 

[Harry Knutz]

Flowback can be common around the firing pin hole. If everything else is working as it should and it bothers you then have the firing pin hole bushed.

Exactly, This is what I have been saying, It's not a problem until it Pierces/Blanks Primers, I wouldn't worry about it until it does. People get their bolts bushed for a reason.

 

[Harry Knutz]

Here you go! This is from Gre-Tan Rifles in Colorado:

Bush Firing Pin Hole & Turn Pin | gretanrifles

Read complete description before sending in your bolt.Please do not click on add to cart. There is no need to call us, just send in your bolt, disregard "Contact us to Purchase" unless you have questions about our service. Do not forget your contact information (name, phone number, address, and...

www.gretanrifles.com

Corrects your cratering and piercing problems.



BUSHING FIRING PIN HOLE & TURN PIN $135.00 + Shipping. OUR WAIT TIME IS 25-50 WEEKS


How to send your bolt in:
You can send your bolt a long with the firing pin assembly, snail mail, priority mail, UPS, but DO NOT USE FED-EX (We have problems with them delivering to our shop). Please include your name, phone number, and return shipping address, and a note as to what you want done. We can overnight them at your expense. Check, money order, or credit card is fine with us.

$135.00 Bush firing pin hole & turn pin per bolt.

If you bolt has fire cut damage to the bolt face, additional charges will apply to clean up this damage. This is because the small busing diamater is smaller than the primer.



We no longer re-bush bolts that have been bushed by someone else. My procedure is not compatible.

Below are shipping costs when shipping one or two bolts without & with insurance.

Send to: Gre'-Tan Rifles, 24005 Hwy. 13, Rifle CO. 81650

 

[JAYgs8163]

Gre-tans books have been closed for months.

 

[Harry Knutz]

I know, I was pointing out that Greg says in his listing for Bolt Bushing, That it Corrects your cratering and piercing problems.

I know one thing for sure, Cleaning your barrel isn't going to fix it!