Bolt Sizes

[Goose Cracker]

I was packing up a couple bolts to be sent off to be jeweled and noticed that my son's CZ in 6.5x55 has a much bigger bolt than my Kimber in 30'06. Much beefier. His scoped rifle weighs a couple pounds more than mine as I recall. Just thought the size difference was interesting!

 

[BeeMaa]

You should be proud that your son has such a big...bolt.

 

[Goose Cracker]

@BeeMaa Ok, ok, I totally should have seen this coming, yet I didn't.

Not as sharp as I once was!

 

[WebleyGreene455]

You should be proud that your son has such a big...bolt.

It's not the length that matters, it's how you use it. Girth and stamina are also important.

 

[Newboomer]

What kind of bolt we talking about here?

 

[Goose Cracker]

Well, I was simply comparing how much bigger/beefier the CRF bolt was for a CZ 6.5x55 (bottom bolt in pic above) versus a Kimber 30'06 and *some* people had to go and make it all creepy.

 

[Ridgewalker]

Back to your original observation, CZ is noted for their robustness, while Kimber is noted for being svelte.
Both seem to be strong actions. Just depends on what one prefers. I’m a 5’7” 153 lb a bit long in the tooth and hunt at higher altitudes, thus I prefer the more svelte rifles. I can pad my shoulder during load development and practice, then leave the extra padding at home while climbing at 9-10,000 feet.

 

[Ray B]

The size of the bolt body wouldn't affect the performance as much as the strength of the bolt face and locking lugs. The function of the portion of the bolt back of the lugs provides for the firing pin system, the sear and sufficient length to operate the magazine. Since there are minimal forces on this portion, a lot of it can be machined away for those that want a lighter firearm. Natural competition reduces waste so one would expect the trimmer bolts to have the final say in matters of continued existence.

 

[BeeMaa]

@BeeMaa Ok, ok, I totally should have seen this coming, yet I didn't.

Not as sharp as I once was!

Sorry man, I read it and just couldn't resist.

Glad you could roll with it.
Sometimes we get so one tracked on a path, we aren't really thinking.
Guilty myself...several times actually.
Cheers.

 

[Alistair]

I expect that CZ simply use a single size of bolt and associated machining dimensions across a wider range of calibres than does Kimber.

The bolt not only seems chunkier (possibly giving the option to use a single size bolt body and action dimension for standard and magnum bolt faces), it also seems longer than the kimber. I expect that dimension bolt is used by CZ for both long and magnum action lengths. Out of interest, would the cuts in the 6.5 CZ allow say a 375 to be inserted into the magazine well?

 

[Jeffrey]

Alistar,
The CZ550 in 6.5X55 used the “550 Medium” action, essentially the old BRNO 600 ie 30-06 length action. However, it is a little long for a standard length action and you can sort of squeeze a 375HH in the top.

The 375HH CZ action is noticably longer.

 

[Goose Cracker]

Update: Just received the two bolts back from customjewelshop.com and think they turned out great. In addition to jewelling the bolt body they also did the extractor. Very happy customer. Pretty inexpensive also - $129 including return shipping for two bolts. Really good communication. Now I'm going to end up doing this with each of my rifles.

No affiliation with these guys, just thought I'd share a good experience.

 

[JimP]

Beautiful, I remember reading how to do this years ago in a old Shooting Times magazine but never had the nerve to try and do it myself. But I also never had a drill press to do it with.

I may be looking them up

 

[Goose Cracker]

Received four more bolts back from Custom Jewel Shop/Front Towards Enemy Firearms. Really nice work and terrific folks to work with. From L to R: Kimber 257 Roberts, Kimber 416 RM, CZ 550 375H&H. Not pictured, Sako 85 338 Fed which also turned out great.