Miroslav

I'm sorry, my sarcasm wasn't coming through.

This spring is (according to the designer) what keeps the bolt from rotating in the bolt carrier, before it has moved all the way forward to the chamber.

https://ibb.co/K5Xs4zV
 
<a href="https://ibb.co/K5Xs4zV"><img src="https://i.ibb.co/mRGyZFh/APED.jpg" alt="APED" border="0"></a>
 
I don't think they'll ever get anywhere with this.
 
 

When your ammobox is lit.

I find that somewhat hard to believe considering that German SOF selected the HK416A7 instead of a Haenel.

Nikita Buyanov, CEO of Battlestate (Escape from Tarkov developers) playing with AK-Evo. It have some new features, including new trigger group and ambi controls for firemode/safety

 

 
 

What I said was misleading, sorry. All of my rifle designs collapse the spring into the bolt carrier and there is no length behind the bolt at full rearward extension where the spring lives. 
 

No, I did not. Bolt assembly and bolt are not the same thing. I'm talking about two separate properties, that of the bolt carrier length needed and that of the bolt extension during unlocking.
 

The F-5 does this. It still follows this rule.
 
 
I think you just didn't understand what I was saying, which is largely my fault. I said a lot of things in a confusing way because I didn't pay enough attention to my composition when I made my reply.

 

You can see how the F-5 takes great pains to telescope the hammer above the magazine:

The German Assault Rifle 1935-1945
 

U.S. İnfantry Weapons of WWII

İtalian small arms of WWI and WWII

That's interesting.
Why wasn't the turning point when russian soldiers invaded Crimea and parts of Ukraine under the letter that Yanukovych asked Putin to send troops there.Later, no surprise that the letter which was presented at U.N by Churkin was a fake and after that Churkin died and Kremlin now denies they got any kind of letter/statement.

SVDM

https://www.reuters.com/article/us-germany-armsexports/german-government-will-ban-small-arms-exports-to-non-eu-nato-countries-report-idUSKCN1TP1OZ

You might consider using a linear hammer arrangement like the vz. 58. In this arrangement, the hammer rides in the BCG rather than the receiver, and catches on a spring-loaded element in the receiver. Where it differs from a Mauser-esque striker arrangement is that it is a separate piece from the firing pin, and impacts it like a traditional hammer.

With this arrangement, you could have the hammer cock and make up the distance between the back of the BCG to the FCG. Then the hammer collapses into the BCG minimizing its length and therefore the length the receiver has to be to contain the action's stroke.

Linear hammers do have some disadvantages - notably they load in the forward stroke using energy from the recoil spring, rather than on the rearward stroke using propellant energy. This means if you're not careful about your spring weights and mass ratios you could end up having trouble with failures of the bolt to close. The vz. 58 for example sometimes experiences this.
 
As for firing pin retention (your actual question!) maybe try what Glocks have on their slide and use a sliding plate?

I found an answer to my own question, that I think could be satisfactory. The ARX rifles from beretta has a cut in the cam pin. The firing pin spring keeps the firing pin in a position that holds the cam pin in place, but if the firing pin is pushed in, the cam pin can be removed. I could do some variant of this.
 
I also need a way to keep the firing pin from reaching the primer if the hammer is dropped prematurely. With a carrier mounted firing pin, this is not a problem. With a bolt mounted firing pin, this has to be addressed. The M14 has a tab sticking out radially from the firing pin. That tab has to go through a slot in the receiver for the tip to hit the primer, but the firing pin rotates with the bolt, and the tab won't line up with the slot unless the bolt is in the locked position. The whole point of mounting the firing pin in the bolt was to shorten the bolt carrier, so I don't want a part of it sticking out. rearwards to block the hammer...
 
Any other ways of doing this than adding a bunch of small parts to the trigger group?
 
 

Top Six Cartridges for Don Ward
6) 30-30
5) 30-30
4) 30-30
3) 30-30
2) 30-30
1) 30-30
Cause that's all my rifle can hold.

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