Author Topic: 1377 new breech  (Read 5137 times)

Offline jz2

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1377 new breech
« on: February 26, 2010, 03:29:32 PM »
I just put a crosman steel breech on my 1377 - I know that the crosman breech is not the "cool" breech, but I gotta tell you.  it makes the gun look 100% better.  tomorrow we'll see how it shoots.

Offline lillysdad621

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Re: 1377 new breech
« Reply #1 on: February 27, 2010, 12:20:53 AM »
you'll love it, and yes... the crosman breach is the best breach, in my eyes. (i got 2 and they make the pistol/rifles so much more enjoyable...)

Offline lillysdad621

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Re: 1377 new breech
« Reply #2 on: February 27, 2010, 12:22:14 AM »
Oh yeah... be careful when you change it, there is a small screw that secures it to the airtube. DONT STRIP IT. do not over tighten it as it will strip and they are a *_*_*_*_*_* to get out and to find.

Offline Bentong

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Re: 1377 new breech
« Reply #3 on: February 27, 2010, 01:44:43 AM »
Did you get the other cool stuff to make it shoot to 800+fps. Pivot pin is a must replace for it tends to slide out that's why i replaced it with a solid pin from Mellon.

Offline jz2

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Re: 1377 new breech
« Reply #4 on: February 27, 2010, 03:16:37 AM »
one is stock other than the breech.  the other 1377 has a solid pin.  that one will also get longer barrel, flat top piston and valve, mellon bolt, lighter valve spring and lighter sear spring.   hope to get to it this weekend.

Offline 1377x

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Re: 1377 new breech
« Reply #5 on: February 27, 2010, 06:22:40 AM »
a mellon solid pin is a must especially if you are modding just got a second today
and those numbers are real

Offline 1377x

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Re: 1377 new breech
« Reply #6 on: February 27, 2010, 06:25:19 AM »
Quote
jz2 - 2/27/2010  10:16 AM

one is stock other than the breech.  the other 1377 has a solid pin.  that one will also get longer barrel, flat top piston and valve, mellon bolt, lighter valve spring and lighter sear spring.   hope to get to it this weekend.


good luck on your project you will be very happy when done
thats how mine is set up

Offline Bentong

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Re: 1377 new breech
« Reply #7 on: February 27, 2010, 10:10:27 AM »


Looks like you got most of what's needed for the mod. I got my Flat top, SS breech screw & 8" LDC from > http://airgunartisans.com/AAACCustom.htm , Solid pin from Mellon and the rest from Crosman. I chopped the 24" 1760 barrel to 18" because I read that 18" is max and any longer slows it down for my application. I Flatten the OEM valve after I ordered another one just in case I mess it up. Lighten up the spring (very light) and open up the porting and the valve front hole just a tad bit and used poly tube for seal. The Hammer spring has to be stiff but I opted out to a power adjuster from Mellon to adjust spring to dump to 20-25pumps. Before the adjuster..I get 2 shots at 20 pumps, 1st was 692fps and 732fps with 7.9 CPHP. With spring adjusted for 20 pumps I got 857fps. I backed the adjuster off to dump at 15 to preserve the valve striker. SO at 10 pumps I get 704fps, 12 -724fps, 15 - 735.5fps. When plinking I just pump her 4-5 and that's easy pumping (1389 pump arm makes it more solid to pump). You got to adjust the flat top right with right spring combo and it will be pumping friendly. The only problem I got know is my other springers are gathering dust for I find it harder to shoot know and noisy. I guess I got spoiled with this one for it's light, got raised cheek and quite (only hear the hammer spring and pellet hitting target).




Offline sshewins

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Re: 1377 new breech
« Reply #8 on: February 27, 2010, 12:31:33 PM »
That is sweet!!  I like the look!  I'm guessing its .177?
Scott




Offline Bentong

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Re: 1377 new breech
« Reply #9 on: February 27, 2010, 02:52:52 PM »
Yup that's .177. Shooter from this guy shot 983.8 fps with 40 pumps. Too much for me worn out arms >>> towards the bottom post >>>>  http://www.network54.com/Forum/275684/thread/1264815181/1377+MOD

Offline sshewins

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Re: 1377 new breech
« Reply #10 on: February 27, 2010, 02:59:41 PM »
Oh man!  There are some rifles that don't shoot that fast!

Makes me wonder, Bentong, if you put a touch of lube on the spring, do you think it would quiet down even further?  No idea if its even possible or feasable, just askin.  Or would grease on spring slow it down (fps) too much?
Scott




Offline Bentong

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Re: 1377 new breech
« Reply #11 on: February 27, 2010, 03:18:23 PM »
I actually Moly lubed the front and back of the hammer spring. The noise is coming from the hammer when it hits the valve pin. Spring tar will slow slow it down.

Offline sshewins

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Re: 1377 new breech
« Reply #12 on: February 28, 2010, 06:00:05 AM »
OK, I wasn't entirely sure.  Makes sense though.
Scott