Unexpected problem re; new barrel

[Nate]

My first attempt at installing a new Douglas barrel on an old receiver has gone very well except that my gas cylinder will NOT fit. It is so tight on the splines that tapping with a block of wood is useless. What has gone wrong here?

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[Texasflyboy]

My first attempt at installing a new Douglas barrel on an old receiver has gone very well except that my gas cylinder will NOT fit. It is so tight on the splines that tapping with a block of wood is useless. What has gone wrong here?

I don't think anything is "wrong" per se, but have you measured the barrel OD on the old barrel at the splines v.s the OD of the new barrel?

A new Douglas barrel may be slightly oversize in OD to allow the tightest possible fit of the gas cylinder to prevent sight movement once mounted.

I think your problem is actually a good one. I would carefully measure the two OD's and then file or stone or both to get a nice tight fit on the barrel splines.

When I rebarreled my DCM M1 back in the early 90's the replacement barrel (a custom one by one of the big mfg's) was super tight. I just filed and stoned and filed and stone until I got a near perfect fit.

That M1 is still a tackdriver.

[Dave Waits]

What Tex said! we should all have that problem!!!

[Nate]

Thanks Tex, I didn't expect so much hand fitting. Even the handguards with the stock set have to be modified, especially the rear one. What happened to Eli Whitney and interchangable parts?

[rider]

If you bring the barreled receiver to a Gun Show, you may be able to find a GC that goes on easier; just make sure that the bore is still within spec. As for the HGs, maybe your Douglas barrel is not GI profile?

[barkerwc4362]

The Douglas barrel is more than likely one of their "heavy" match barrels. Champions Choice put a 308 on one of my receivers. They are a really nice barrel, however, they are not "USGI" contour. The rear handguard will have to be modified for the fuller contour of the Douglas barrel from the receiver to the barrel band. I have another Douglas fitted but not final chambered on another of my receivers in 30-06 that is of the same "heavy" contour that I need to finish. Just remember these barrels make the rifles they are fitted to not JCG eligible as a service rifle. They are now a "Match" rifle.

Bill

[Nate]

My local M1 guy demonstrated that I was simply too gentle in banging the thing on. I have always been over careful when fitting parts, having seen horrible results from being too heavy handed.