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L Cazador

Large firing pin vs small primer

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It appears there are many misinformed people regarding large firing pins on small primers. Pretty much there's not much advantage of a small primer vx. a large primer pocket unless you're shooting paper and probably only benchrest paper. And you better be a great wind reader to see that advantage! A large firing pin on a small primer is not a good idea. Law of inertia says it's wrong. Take your pick. It isn't worth a disabled rifle in the middle of a hunt or a match! Not speak of what can happen to your eyes!! IMG_3503.JPG.cd612b66fc1e8cb01ca5d279547544e6.JPG 

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6 hours ago, Mike S said:

I see the advantage in a substantially increased case life with my .308 brass. 

 

Better case life by going to a small primer pocket, great stuff! Since better case life is usually due to good reloading technique like not over sizing brass and shooting lower pressure loads that's fantastic! By the way I've been using UBR 308 small pocket brass for 30+ years.

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6 hours ago, L Cazador said:

Better case life by going to a small primer pocket, great stuff! Since better case life is usually due to good reloading technique like not over sizing brass and shooting lower pressure loads that's fantastic! By the way I've been using UBR 308 small pocket brass for 30+ years.

It is! To easily get competitive velocities with 155s in a Palma rifle along with long case life is great. Not oversizing brass and having a die matched to a tight reamer is not difficult.

Not sure I understand what you are alluding to with your "law of inertia" comment. Firing pin bounce? 

Sounds like you get a lot of use from your UBR brass, that's fantastic. What are your thoughts on the smaller flash holes such as in the Lapua Palma brass for example?

 

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42 minutes ago, Mike S said:

It is! To easily get competitive velocities with 155s in a Palma rifle along with long case life is great. Not oversizing brass and having a die matched to a tight reamer is not difficult.

Not sure I understand what you are alluding to with your "law of inertia" comment. Firing pin bounce? 

Sounds like you get a lot of use from your UBR brass, that's fantastic. What are your thoughts on the smaller flash holes such as in the Lapua Palma brass for example?

 

As you see above in the pic I posted it's primer bounce off the firing pin (inertia) and there isn't enough support around the primer to support it with a large firing pin. Lapua small primer pocket gives me lower and more consistent ES.  You lose that consistency and ES with a large firing pin and large primer.IMO it's about barrel harmonics! I blanked my first primer back in the early 90's in a 223AI. Now you would think a Remington 40X would have a small firing pin for that former cartridge I bought it in (222), nope! I had the firing pin turned to .062" and the bolt bushed for it, wow that 223AI shot like never before! ILike I said before in another post you're not going to see the difference if you're not a good wind reader! 

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By the way I change firing pin springs every 1000 rounds for my match rifles. Consistency is next to Godliness! LOL!

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Can't see the picture very well as I am on my cell phone and out of town. I'll have to check in a couple of days. 

I have well over 3000 hot small primer Palma loads thru my 40x Palma .308 with no blanking issues and factory pin.  5000 plus thru my M70, but did have the pin bushed on it. It's now my back up rifle with a fresh Obermyer on it. Plenty of better wind readers than me, but I did earn my long range High Master card at 1000 yards with a .308, 155s and irons. Scopes are a crutch😉.

 

 

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SDs are typically in the 7-8 fps range for 20+ shots as measured at the 1000 target face with my e target. 

I stuck with the standard weight pin and 24 pound spring in the 40x. 

Glad you were able to get your 40x sorted out.

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1 hour ago, Mike S said:

SDs are typically in the 7-8 fps range for 20+ shots as measured at the 1000 target face with my e target. 

I stuck with the standard weight pin and 24 pound spring in the 40x. 

Glad you were able to get your 40x sorted out.

shooting iron sights are but a dream for me. Nowadays it's a 15X55 nightforce for me!LOL! I shoot 30BR UBR bench and 1000 yard BR. And it's BATs and Kelblys! Although my 40X 30BR still burns alot of Arse! My 40X has been a 308, 6BRA, and now a 30BR SRBR with 4K rounds in the 30BR and still shootin' in the 1's at a hundred! Fun stuff! 

IMG_3505.JPG

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