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Airguns by Make and Model => Crosman Airguns => Topic started by: NickB79 on June 08, 2014, 02:34:49 AM

Title: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: NickB79 on June 08, 2014, 02:34:49 AM
If I start with a Crosman Morning Play pack, which comes with a steel breech and carbine stock, and then add an 18" barrel, what other available mods offer the easiest way to an 10-12 fpe bird buster?  I'd like to stick with .177-cal for the flatter trajectory and cheap pellets.

Thanks!
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: BenjiHunter on June 08, 2014, 02:36:32 AM
Flat top valve and piston.
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: NickB79 on June 08, 2014, 03:06:01 AM
And that's all?  Just plug and play?

I think I can do that :-)
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: rrdstarr on June 08, 2014, 03:23:24 AM
And that's all?  Just plug and play?

I think I can do that :-)

And a RVA(Rear Velocity adjuster) which I sell several models of! ;)
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: BenjiHunter on June 08, 2014, 05:20:18 AM
And that's all?  Just plug and play?

I think I can do that :-)
Yeah, that's it.
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: DavidS on June 08, 2014, 09:32:44 AM
A better piston will not get you 12FPE by itself.

Easier than the Flat Top Piston, and likely to get you closer to your goal is:


There are other mods to get even more power, thought keeping it simple that should get you pretty close to your goal.

If not yet done, I would recommend recrowning the barrel, pollishing the trigger/sear and sear/hammer contact surfaces, and installing a lighter trigger spring.  There are a few other things that can make the trigger even better though that is a good start.
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: breakfastchef on June 08, 2014, 10:14:15 AM
10-12 fpe is a pretty high benchmark. Forget the 18" barrel and go with the 24". You are going to need it.

Going to need to do valve modifications, too.

http://www.airgununiverse.net/13xxvalve.html (http://www.airgununiverse.net/13xxvalve.html)

Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: BenjiHunter on June 08, 2014, 03:52:59 PM
Mine has a FT valve and piston, steel breech and a 16" barrel.
I don't have a chrony but it blasts thru a 1" phone book with 15 pumps.
I think that's probably 12FPE or more.
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: BillK on June 08, 2014, 04:38:48 PM
I have a 1377 with an 18* barrel, Mountain Air flat top piston & valve, 5/32" transfer port, extended bolt.  Stock hammer & valve spring.
15 pumps w/8.18g pellet @757 fps = 10.4 FPE    Same at 20 pumps is 11.1FPE

(http://i129.photobucket.com/albums/p212/wwk1a/1377%20carbine/100_05821.jpg)
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: BenjiHunter on June 08, 2014, 04:47:56 PM
I'm sorry.
I missed the fact that you wanted a .177.
Mine is a .22. :-X
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: K.O. on June 09, 2014, 06:16:23 AM
Not exactly simple but not to difficult either.

mount it all on a 66 pump tube... ;)
Title: Re: What's the easiest way to build a 12 fpe, Crosman 1377 carbine?
Post by: DavidS on June 09, 2014, 09:18:47 AM
Not exactly simple but not to difficult either.

mount it all on a 66 pump tube... ;)
+1

Though the only good .177 Crosman I have left is a 66, so I be biased.