How to shim a bolt to reduce headspace- Brno4/CZ452,455

[@gordy1961]

Bought a set from Lance and he sent all the way to Blighty for just an extra dollar! What a lovely guy.

[@inrangerimfire20two]

Legend!

[@CHenry1951]

Nice , can't wait to see the results

[@inrangerimfire20two]

Me neither!

[@ctom4103]

Just a thought. On a Brno or 452, if you unscrewed the barrel and turned the tenon down to achieve proper headspace the slots for the extractor and case holder wouldn’t line up properly. So the shims are possibly the only way to do it.

[@inrangerimfire20two]

Hey there, the shims are the easy way to do it. One would need to follow the same procedure as if installing a brand new barrel if one went the barrel method to adjust the headspace, but it is most certainly doable, and the best way, but not at all easy for the average person

[@johnmal801]

Excellent video! Thanks.

[@inrangerimfire20two]

Thank you! Let me know how your project goes

[@jonleone777]

Correct me if im wrong,but dont you have to headspace to a particular ammo.

[@craftyha]

Is a scope base available like the one seen on the rifle in this video for a winchester 75 made in 1940? I have 2 original scopes but I'd like to put a 1 piece base and a leupold gold ring on it.

[@inrangerimfire20two]

Hey, Yes it is. It is made by EGW and mounts using the factory rear sight block holes.

[@davidsand7905]

Good video. But I have one question. How tightly does bolt closure become when you've reached the proper headspace?

[@inrangerimfire20two]

Great question and I will be demonstrating that during the range test video, but the long and the short of it is- it is based on the thickness of your shim. The thicker the shim, the more “tighter” it will feel. This is important because a thicker shim doesn’t necessarily improve groups, it’s all about a balance. That’s why I say start thin and work up.

[@tv-cx8gv]

Show us the results??

[@inrangerimfire20two]

I did already kzbin.info/www/bejne/bKGTm52kjLN4rrM

[@TheWilferch]

Hmmm..... let me ask this--> OK, I get how this works, BUT.... let's look at the bolt-face. It can be described as a "depression-in-a-cylinder". The breechface.... in my words, the plane where the firing pin protrudes from. This breechface "depression" usually determines headspace ...IF....the remainng surounding metal....the "cylinder"....hits the immovable portion of the receiver. So.....my question is.....this shimming seems to work ONLY if the surrounding cylinder STILL has some amount of "Gap" axially forward.... toward the immovable portion of the receiver.....right?. If not.....we can't shim this.....right? I always thought a shim kit would be varyng thicknesses of shims that is placed directly upon the breechface. Does this make sense to you as a "visual" explanation?....and if so....can you comment?

[@inrangerimfire20two]

The shims work by allowing one to close the available distance between the bolt face (adjustable) and breechface (non) and therefore allowing the rim to be pushed forward- driving the round deeper into the chamber

[@TheWilferch]

@@inrangerimfire20two ....I guess we're saying the same....but to use my own words so that it's more understandable ( to me and maybe also to others).... the boltface must therefore have some airspace in front of it when adjusted for headspace....otherwise shimming would not allow full bolt closure...meaning the boltface would otherwise hit the "receiver" or "backside" of the barrel. So...let me ask....how can we adjust headspace ( if at all) on a Savage MKII design, where the bolt handle is not removable, and the headspace is determnined by the backside of the bolt handle riding against the receiver "slot" in which it rides?

[@inrangerimfire20two]

@@TheWilferch yes we are saying the same thing. The bolt/handle etc on a MK2 is removable and I have shimmed one before but it isn’t recommended. I think there are some pics on Triggershims website showing how it’s done. I may even have an early video on it when I did it on my Lakefield 91TR

[@TheWilferch]

@@inrangerimfire20two...thanks....I'll check into this.....thanks for responding with detail.