1377 mod parts..



Author Topic: 1377 mod parts..  (Read 3135 times)

Offline Pete

  • Old Timer
  • ******
  • Posts: 2265
1377 mod parts..
« on: November 06, 2010, 05:57:08 PM »
Hi...
I have a 1377 converted to .22 12" barrel
& crosman steel breech...
thinking of a flat top piston & modded valve from
AC custom parts...
Is the power increass worth putting them in ?
EXSPERIANCE - being able to recognise your mistake the second time you make it....

Career Infinity .22 PCP
Hatsan Mod 55 .177
Hatsan Mod 75 .22
Hatsan Mod 99 .177
Kral Underlever .177
Gamo Hunter 440 .22
Others...

Link to other hobbie's
My XT660 side car build on Adventure rider...
http://www.advrider.com/forums/showthread.php?t=775145

Offline 1377x

  • Born To Be A Star!
  • Old Timer
  • ******
  • Posts: 3683
  • closed mouths dont get fed!!!
Re: 1377 mod parts..
« Reply #1 on: November 06, 2010, 09:17:39 PM »
Hi...
I have a 1377 converted to .22 12" barrel
& crosman steel breech...
thinking of a flat top piston & modded valve from
AC custom parts...
Is the power increase worth putting them in ?
YES!
imo it should be the first mod followed by the trigger as you have the steel breech already
you wont be disappointed
if your shooting 550fps(10x) now it can go up to as much as 650+fps(10x) with other mods maybe higher so in other words up to 100+ fps increase
so make haste get your flat top set up and report back  ;D ;D
« Last Edit: November 06, 2010, 09:31:33 PM by 1377x »
short list
1) get up!
2) survive!!
3)go to bed!!!

Offline mr007s

  • Plinker
  • **
  • Posts: 266
Re: 1377 mod parts..
« Reply #2 on: November 06, 2010, 09:21:34 PM »
Howdy Pete, good question. Having just gone thru with modifying a 1377 I have some thoughts regarding your query. Are you planning to target shoot, critter hunt, or both? If it is just for plinking or punching paper I would say no, save the bucks. My stock .177 cal  sent 8 grain pellets at around 510 fps with 10 pumps. If I was shooting 10 meter range I usually only pumped her 4 to 5 times. Longer distances got more pumps.
 I documented speeds and groups for several brands of ammo so to have a bench mark to compare to.
upon completion my fps increased to 670 with the 8 grain exact. Your numbers will be some different being you have the 22.

My thoughts are the expense was worth while in my case. Part of the gain was an increase in barrel length of 5 inches. AC Customs supplied the barrel, flattop piston and valve.

My feelings are the trigger spring and guide are a required upgrade with some sear polishing and tighter fitting pins, around .128" worked in mine. If you do the piston/valve mod with porting from AC the hammer spring and guide will also be a good choice.

These few things struck me as being the most beneficial as I pursued my quest for a more powerful and accurate shooter.

Hope this helps, I am sure others will be along with more thoughts for you.
mr007s,,,,,Life is Good

Offline Bentong

  • Sharp Shooter
  • ****
  • Posts: 782
Re: 1377 mod parts..
« Reply #3 on: November 06, 2010, 09:52:10 PM »
Mine with 19" barrel (177) & flot top and modded valve, 3 pumps = 436fps (7.9 CPL), 6 = 600fps, 10 = 707fps, 15 = 783, 20 = 828fps. I used Mellon's power adjuster instead of a stiff spring to dumps air form 15+ pumps. Every mod was worth the expen$e$.

Offline Pete

  • Old Timer
  • ******
  • Posts: 2265
Re: 1377 mod parts..
« Reply #4 on: November 07, 2010, 12:12:21 AM »
Hi..

Kool guys..Thanks..
I will push the appropriate buttons..
I will mainly use it for starlings, will
be a nice light gun to walk around the
vineyards with..


LOL..Just my luck... >:(
went to do the order thing  BUT
he's no longer excepting orders till
the 4/11/2010 ...but its the 7th ??? ???

waiting waiting waiting etc.. :'( :'( :'( :'(
« Last Edit: November 07, 2010, 12:22:12 AM by pete »
EXSPERIANCE - being able to recognise your mistake the second time you make it....

Career Infinity .22 PCP
Hatsan Mod 55 .177
Hatsan Mod 75 .22
Hatsan Mod 99 .177
Kral Underlever .177
Gamo Hunter 440 .22
Others...

Link to other hobbie's
My XT660 side car build on Adventure rider...
http://www.advrider.com/forums/showthread.php?t=775145

Offline Millipede

  • Sharp Shooter
  • ****
  • Posts: 591
  • Aim small, miss completely.....
Re: 1377 mod parts..
« Reply #5 on: November 07, 2010, 05:25:16 AM »
Mine with 19" barrel (177) & flot top and modded valve, 3 pumps = 436fps (7.9 CPL), 6 = 600fps, 10 = 707fps, 15 = 783, 20 = 828fps. I used Mellon's power adjuster instead of a stiff spring to dumps air form 15+ pumps. Every mod was worth the expen$e$.

what mods were done to your valve? im thinking of making mine a .22 also and was wondering if i should just get a FT piston/valve with the modified port. or if i should go all out and have it bored out for increased air volume in the chamber. like this here: http://www.rateacomic.com/AM/13xxvalve.htm
here's another link i like to look at too http://www.mp661k.com/sitedocs/13xx_HotRod.pdf

my .22 will have a 14 inch barrel and i want maximum power for it  :) 
          is boring the valve worth it, or does it really just equate to even more pumping? since adding volume would require more air to reach the same pressure, right? or does more air mean more pressure/force?
     and, from what im thinking in my head, the pellet would have already left the barrel by the time all that air is released from the valve. does that matter?
      or is it just the initial amount of pressure/force in that instant the valve releases the air. so then, more volume would be a good thing?

cole5169

  • Guest
Re: 1377 mod parts..
« Reply #6 on: November 07, 2010, 08:19:24 AM »
Hi...
I have a 1377 converted to .22 12" barrel
& crosman steel breech...
thinking of a flat top piston & modded valve from
AC custom parts...
Is the power increass worth putting them in ?

You're describing my latest 13"77" build exactly.
I also converted it to a steel breeched, 12" .22 barrel.
I ordered the brass flat-top piston and modded valve from Alejandro, and it made a very noticeable difference :)
He does really nice work.  Totally worth it.

Offline Bentong

  • Sharp Shooter
  • ****
  • Posts: 782
Re: 1377 mod parts..
« Reply #7 on: November 07, 2010, 08:33:57 AM »
Mine with 19" barrel (177) & flot top and modded valve, 3 pumps = 436fps (7.9 CPL), 6 = 600fps, 10 = 707fps, 15 = 783, 20 = 828fps. I used Mellon's power adjuster instead of a stiff spring to dumps air form 15+ pumps. Every mod was worth the expen$e$.

what mods were done to your valve? im thinking of making mine a .22 also and was wondering if i should just get a FT piston/valve with the modified port. or if i should go all out and have it bored out for increased air volume in the chamber. like this here: http://www.rateacomic.com/AM/13xxvalve.htm
here's another link i like to look at too http://www.mp661k.com/sitedocs/13xx_HotRod.pdf

my .22 will have a 14 inch barrel and i want maximum power for it  :) 
          is boring the valve worth it, or does it really just equate to even more pumping? since adding volume would require more air to reach the same pressure, right? or does more air mean more pressure/force?
     and, from what im thinking in my head, the pellet would have already left the barrel by the time all that air is released from the valve. does that matter?
      or is it just the initial amount of pressure/force in that instant the valve releases the air. so then, more volume would be a good thing?

AC do sell power modded valves or can send your valve for $5 IIRC. I open up the front hole for more air and easy pumping along with light spring...just enough to close the check valve, have to cock first before pumping. Removed the 90 degree corner. Cutting threads to increase volume makes you only pump more to fill valve harder for same results...i think needed for co2 shooters 22XX.

Offline sshewins

  • Plinker
  • **
  • Posts: 212
  • Real Name: Scott
Re: 1377 mod parts..
« Reply #8 on: November 07, 2010, 01:19:26 PM »
Hey guys, is the steel breech really worth the time/effort?  If your going from .177 to .22 I think you'd have to anyway, right?  Does crosman sell the steel breech?  Thanks
Crosman 2289g.     24" barrel, steel breech, CP 3-9 X40, polished trigger, AC Customs FT piston, trigger spring w/ guide,  7" LDC, Airgun Alchemy FT valve, pivot pin, extended probe bolt.

Offline mr007s

  • Plinker
  • **
  • Posts: 266
Re: 1377 mod parts..
« Reply #9 on: November 07, 2010, 03:23:17 PM »
Yes to change calibur and yes to Crosman having for sell.
mr007s,,,,,Life is Good

Offline sshewins

  • Plinker
  • **
  • Posts: 212
  • Real Name: Scott
Re: 1377 mod parts..
« Reply #10 on: November 07, 2010, 05:14:42 PM »
Thanks.  Is the crosman steel breech and better/worse than say, crooked barns?  Gonna guess the crosman would be cheaper...
Crosman 2289g.     24" barrel, steel breech, CP 3-9 X40, polished trigger, AC Customs FT piston, trigger spring w/ guide,  7" LDC, Airgun Alchemy FT valve, pivot pin, extended probe bolt.

Offline 1377x

  • Born To Be A Star!
  • Old Timer
  • ******
  • Posts: 3683
  • closed mouths dont get fed!!!
Re: 1377 mod parts..
« Reply #11 on: November 08, 2010, 10:43:18 AM »
Thanks.  Is the crosman steel breech and better/worse than say, crooked barns?  Gonna guess the crosman would be cheaper...
its personal preference
imo they are both great. i think the crocked barn you can use the rear site on it i f dont want t use a scope
short list
1) get up!
2) survive!!
3)go to bed!!!

cole5169

  • Guest
Re: 1377 mod parts..
« Reply #12 on: November 08, 2010, 11:07:49 AM »
. . .  If your going from .177 to .22 I think you'd have to anyway, right?  Does crosman sell the steel breech?  Thanks

You don't need to change the breech to change caliber.  Just the barrel and the bolt. :)

That said, I like the steel breeches; they hold the barrel more firmly, and give you dovetails.
-Joel

Offline sshewins

  • Plinker
  • **
  • Posts: 212
  • Real Name: Scott
Re: 1377 mod parts..
« Reply #13 on: November 08, 2010, 03:46:53 PM »
Ah ok, got it.  I think I'd like the steel breech for the scope mounts anyways.  (sorry, it seems I've hi-jacked the thread)
Crosman 2289g.     24" barrel, steel breech, CP 3-9 X40, polished trigger, AC Customs FT piston, trigger spring w/ guide,  7" LDC, Airgun Alchemy FT valve, pivot pin, extended probe bolt.

Offline Millipede

  • Sharp Shooter
  • ****
  • Posts: 591
  • Aim small, miss completely.....
Re: 1377 mod parts..
« Reply #14 on: November 09, 2010, 01:07:29 AM »
AC CUSTOM PARTS IS OPEN FOR BUISNESS AGAIN!!   YAYAYAAAAY

i just sent him my valve today for mods and im getting a flat top piston and a new trigger spring. someday ill get one of his wire stocks and muzzle brakes. too bad he doesnt make breech's or flow through bolts...  it'd be nice to get all my stuff from one source.

so i'll be getting a long breech from RJMachine and a flow through bolt from mellonair. dont know who to get grips from. i kinda want to make my own. does anybody have any info/links on how to do that?

Offline Pete

  • Old Timer
  • ******
  • Posts: 2265
Re: 1377 mod parts..
« Reply #15 on: November 09, 2010, 01:12:36 AM »
Hi..
he sure is up and running again... ;D
just got a reply from him...will put the
order though....
EXSPERIANCE - being able to recognise your mistake the second time you make it....

Career Infinity .22 PCP
Hatsan Mod 55 .177
Hatsan Mod 75 .22
Hatsan Mod 99 .177
Kral Underlever .177
Gamo Hunter 440 .22
Others...

Link to other hobbie's
My XT660 side car build on Adventure rider...
http://www.advrider.com/forums/showthread.php?t=775145

GTA - The best place for discussion about Air Guns.