Home Forums Hunting & Shooting Custom Rifles & Wildcats Mini-Mauser headspace issue what to do?

I have a High Tech Specialties-stocked Zastava mini-Mauser in .223 Rem that I'm told has excess headspace.

I love the rifle so I figure I could:

1) have the factory 1-in-12" set back and rechambered to standard .223 Rem

2) same as above but .223 Imp 40 Degree (feeding gonna be ok tho?)

3) pick up a relatively inexpensive 1-in-8" twist SS FW contour barrel & do either option 1 or 2

4) get a 6mm barrel & do a 6x45mm

I like option 1 cuz it's least expensive. Option 3 I like best cuz it'll allow me to shoot whatever weight bullet I want. Not sure about #4 because Mag constraints would be tough to abide.

Anyone who has gone to the sharper shouldered Imp 40 degree or a 6x45 in this action?

Unless the headspace is dangerously excessive why not fireform some dedicated brass to it and then adjust your resizing die so that it is only pushing the shoulder back a couple of thousandths.

drover

Just set the barrel back by whatever amount it takes to eliminate the excess headspace. Can't be more than about .010". No need to rechamber. That's the easy fix.

The fast twist barrel would be fun to be sure.

Who told you the headspace is excessive, and how do they know? Before I started dinking around with a favorite rifle, I'd want to be sure there was really a problem with it and not say, an issue with reloads.

Run a 6mm expander ball through the neck. Then partially resize to put a false shoulder on the brass, so that the bolt closes with some effort. Then continue to use that brass, resized in same fashion.

It worked for me when I had a similar problem.

If you're thinking about 1:8 and 75's I think you'll have trouble with mag-box length. Neck-up/neck-down false shoulder on 20 pieces of brass is about a 5 min potential fix and almost free.

I have the 6x45.

If you are looking to wring out every ounce of velocity for bragging rights, its a non starter.

But if you just want to kill stuff inside a couple hundred yards, no problem.

Guy used field gauges. I'd asked if the firing pin was protruding appropriately and he measured that and said it was good.

Interesting thing here is that I ran both reloads and factory through it. Some of the reloads were partially sized cases that'd been run through an AR and were tough to chamber in this rifle, which told me they ought to have been fine for headspace. The firing pin would barely dent the primer.

When I first got the rifle it'd shoot maybe 8/10 of the rounds I put through it, but as time went on it has gone to where I expect it to NOT go off when I squeeze. More than half of the factory stuff I put through it has lightly dented primers and nothing more.

I'm kinda at a loss with this rifle and unsure whether I trust this gunsmith so I am going to pick up the rifle and take it to someone I trust to check things over.

I love the idea of either a 6x45 (I don't care about speed for this purpose) but am going to exhaust options with the existing barrel. I'm always flirting with ideas for the next build before I even have the one before done!

This is a bit of a mystery to me but I absolutely love this rifle so I'm trying to stick it out and get it figured. Such a light weight joy to carry and when it goes bang it hits what I'm aiming at!

Thanks all!

I think I'd send it to ER Shaw for a new barrel as the easy way out. A second option might be a rebore to say 6x45, but not everyone works with bore sizes that small and the barrel would probably still need to be set back.

efw,

Since the reloads had only been partially resized and had been fired in an AR I am not surprised that they were tough to chamber. The hard to chamber could be caused by a slightly longer chamber, or larger chamber diameter, since most resizing dies do not resize the full length of the case, quite often it is necessary to use a small base die to resize brass that has been fired in an AR. As long as factory ammo is chambering without any problems then I would not be concerned about the partially resized reloads being hard to chamber,

But as to your not firing issue - you have had the firing pin protrusion checked so that can be discounted, at least for now. To me it sounds like you have a weak firing pin, the symptoms you describe sound exactly like every weak firing pin issue I have ever encountered.
Firing pin springs are inexpensive - give replacing it as a try before taking more drastic (expensive) steps.

drover

I have three of the Charles Daly mini Mauser, two of which I've built on so far. They all had exceptionally heavy grease over the whole action as well as on the firing pin spring. I don't know if that may be an issue on your rifle but perhaps a thorough cleaning of the bolt may help.

Unless I mis-understood him, he said the rifle accepted a "field" headspace gauge. That ain't good.

If I remember right, some mini-mausers had wylde or nato chambers?

Been using a Rem 660 in 308 since the early nineties. It will take a no go plus several thousandth headspace gauge. Neck sized LC brass until it got snug, then adjust full length size die to bump shoulder. The thing also likes pretty warm loads, on!y ever had one problem with brass,that was what caused the headspace check in the first place. And no, my loads did not cause the problem, it was that way when I bought it.

[quote=Dillonbuck]Been using a Rem 660 in 308 since the early nineties. It will take a no go plus several thousandth headspace gauge. Neck sized LC brass until it got snug, then adjust full length size die to bump shoulder. The thing also likes pretty warm loads, on!y ever had one problem with brass,that was what caused the headspace check in the first place. And no, my loads did not cause the problem, it was that way when I bought it.[/quorete]

Something similar is what I was referring to in my earlier post, I have used a lot of "new" take-off barrels and quite often they would be close on headspace but "just out", so I sized the brass to fit the chamber.

drover

If it shoots tweaking the loading procedures is definitely the least expensive option. If it is really off I would set back the barrel so factory or rounds from other rifles would work in it. As someone posted I would do a chamber cast and compare it to the Wylde or Nato chamber.

If it needs a new chamber the AI or .222 Magnum would clean it up even more or the 6mmx47 version is another choice. Also de-grease the bolt and maybe upgrade the firing pin spring with something like a Wolf spring.