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Crosman 1377, gap between Gmac steel breech and stock barrel

Started by kar120c, March 05, 2017, 08:56:31 PM

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kar120c

I am tuning my new 1377 with Gmac long steel breech, and extended probe. Fitting was easy and the pistol shots well but, I have issues loading pellets.
Pellets tilt when I try to push them into the barrel. The first well known problem is the screw hole, but what I noticed  that there is a gap between the barrel and the breech where pellets stucks.
Take a look at the pic where where there is a good view of the issue.

The breech is mounted in a fixed position due to centering Transfer Port to breech hole and barrel, so I think it is a breech problem.
I ask if others has this issue and if it has been solved.

JMJinNC

Wax over the screw will help. Wax in the gap would also work. I had the gap issue on my LW66 build due to a custom machined barrel. Solved it with a plastic washer at the end of the barrel.

JMJ
John

kar120c

Quote from: JMJinNC on March 05, 2017, 09:20:53 PM
Wax over the screw will help. Wax in the gap would also work. I had the gap issue on my LW66 build due to a custom machined barrel. Solved it with a plastic washer at the end of the barrel.

JMJ

38/5000
I fear that the wax enters the barrel, now I have learned how to load pellet so I can live with it. The important thing is that it does not affect accuracy and power

JEBert

Hi Kar,
I had some pellets hanging up upon loading a 1377 and I polished the breech end of the barrel and the leade.  Have had no more problems since.   Good luck with it!
Many blessings,
Jerry
Jerry
NRA Life Member
USAF Veteran 1973-1977 (43151E) Sgt (E-4)


kar120c

I am curious if the Crosman steel breech has the gap issue. I bought a Gmac because I thought better quality

mr007s


BillK

Have you contacted GMAC and shown them that pic?  I have never had a breech/barrel fit that poorly.  Let them know and you may/should receive a new breech.
West Michigan
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kar120c

Quote from: BillK on March 07, 2017, 05:23:49 AM
Have you contacted GMAC and shown them that pic?  I have never had a breech/barrel fit that poorly.  Let them know and you may/should receive a new breech.

I just wrote, let's see what they say


Sweller

Quote from: kar120c on March 05, 2017, 09:44:06 PM
38/5000
I fear that the wax enters the barrel, ...
Please forgive me for coming in so late, and I'll also apologize for what might be a stoopid question. But ...

Why does the incidental introduction of a small amount of wax in the barrel concern you more than the lead you intentionally introduce? Any wax that does get in the barrel is gone instantly with the first pellet. No?

P.S. I just  checked the gap in my Custom 1740 and it's no where near what yours is. Admittedly though, it's kind of an apple to urchin comparison since I have a Crosman breech. But my barrel is LW.
Stephen Weller
American.
Veteran.
Patriot.