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Inch BOLT in Metric rifle?

EMDII

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There are minor differences in the humps/cams that most of us regard as threats to reliability. The consensus is to change the B/BC together.
 

robmac

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The answer is: you have to try it. I had one in a DSA para I built many years ago (para metric carrier with inch bolt) before I even knew there was a difference. It was one of the best functionning and accurate rifles I ever had. Remember that the para carrier was new and the bolt worn. Does that make a difference? Who knows? My impression is that it doesn't make much difference, but I will say that if given a choice I wouldn't mix and match. I don't anymore - but, obviously, it can work.
 

DT

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When I had Derek at AZEX brl. and put in the locking shoulder in my STG I also had him but in a inch BC/B . The reason being is that the bolt had a two-piece firing pin and the bolt carrier had sand cuts so as to help channel debris.
Do'nt mix-n-match,I checked around alot like you are doing now just to be sure that what I was thinking about doing would really work , but more important be safe.

BEST OF LUCK.
 

bykerhd

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I just swapped an Inch bolt/carrier combo into a metric receiver. They replaced an Imbel set. No particular reason except I had them and I like the look of the sand cuts.
Make sure you check headspace regardless of what combination you come up with. This particular Inch set was British. Checked the combo in another rifle with an Aussie bolt/carrier combo. Significant difference in headspace. The wrong direction.
 

Gun Buff

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I just ordered one from entreprise they did not have a new one in metric and said a inch was the same I ask are you sure and the guy at entreprise said ya.I didn't mess up did I. He also said all the parts would work find. as long as it sets down and headspaces it should be find . Right
 

Falfegnügen

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Watch out for the Indian bolt/carriers. They are single cam, but otherwise look like L1A1 bolt/carriers. As far as I know, all other FALs, including all FN "Metric pattern", Israeli, L1A1's, C1/C2, etc, are double-cam. Thus Ted's advice/warning, best to keep them together as a matched set.

The good news is that the FAL is a very tough and forgiving design, and if there is an issue with bolt/carrier compatibility, it probably won't blow-up on you. Just won't work too well and might get jammed up nice and tight. Which is unlike some other rifles, M14's for instance, which have been known to explode like a grenade when things aren't right. :confused:
 

OODA_Loop

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Thanks. My reason for asking is that TDW has new inch bolts, and I was considering a para for 2nd build - which come, of course, with the bolt carriers, but no bolts. New bolt, new carrier, good thing.

And yes, I do drink ;)
 

chrsdwns

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I have made measurements on inch and metric bolts and they seem to be the same in in all critical areas taking into account production tolerances.

Also, the Canadian bolt and carrier is interchangeable with the Aussie and British SLRs. The Canadian carrier does not have sand cuts is very close to an identical copy of the Belgian Bolt Carrier in all critical areas.

Who is TDW?
 

EMDII

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BlackCat said:
Also, the Canadian bolt and carrier is interchangeable with the Aussie and British SLRs.
They're all Inch-pattern, regulated by agreements between the Australians, British, and Canadians. They MUST work together.

1960 BSA on the right
Low-SN Belgian on left

Notice the internal differences. Yes, they are similar. Have you bet your life on 'pretty close' before?
 

EMDII

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A macro of the internal cuts. The cam humps are slightly different.

As long as everyone has an understanding of likely consequences, we get to chose accordingly.
 

Brian in MN

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Inch bolts are double cam on the middle and sides. Metric bolts are double cam on the middle and single cam on the sides. I would not mix and match. A new bolt is a lot cheaper than a serious failure due to improper fit.
 

Bad Bob

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"BTW - If you are swapping out the bolt/carrier combo on a pre-build FAL, it's a good idea to check your headspace."

Absolutely - try everything you've got while you're checking headspace, and you might get lucky. I've got a British sand-cut bolt carrier w/ bolt that headspaces exactly the same as my Israeli bolt carrier & bolt. Nothing like a spare bolt carrier w/ bolt in time of need!
 

Olaf

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They (DSA) sold a bunch of dsa built IMBEL kits ( IMBEL kits on their dsa receivers) that had aussie bolts in the original carriers ...not that their practices are always without flaw. I have one , it shoots ...
 

GBISHOP

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This is Good to Know. Thinking about putting a new L1A1 bolt onto a Imbel carrier. Either regular or para. Hope it works. New build so it will definitely be head spaced.
 
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