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I've joined the Pumper club ...

Started by tayloriand, July 05, 2011, 08:01:38 PM

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slothart

OK, time for a tear down of my 1377 to see if I have my piston adjusted properly... my numbers are feeling low  :P
Crosman: 1377carbine / Beeman: Tempest / Benjamin: P-Rod, 310 & 342 / Sheridan: Blue Streak & Blue Streak Steroid (both rockers) / AA TX200HC

1377x

Quote from: slothart on July 06, 2011, 03:17:27 PM
OK, time for a tear down of my 1377 to see if I have my piston adjusted properly... my numbers are feeling low  :P
it might be the headspace difference between the two pistons
the valve may need a little more facing
there are many factors when it comes to the valve and piston mods
i have a brass valve self modded that out performs the ac valve and an aluminum valve heavily modded that doesnt do squat 650fps 16" barrel 10 pumps crosman wadcutters.i suspect i need to take a little more material off the valve face
closed mouths dont get fed

slothart

#17
I figure it is worth a look to make sure I have everything adjusted correctly since this was my first build, but if i can't improve my numbers with my current setup, it is no big deal.  As a backyard friendly plinker, it is does the job very well.  Just curious since my numbers seem to be significantly lower then what others are posting. 

If the piston is already adjusted correctly, it gives me something to do with the stock valve I removed and replaced with the Mellon valve.  It will be good to try my hand at modding a valve.
Crosman: 1377carbine / Beeman: Tempest / Benjamin: P-Rod, 310 & 342 / Sheridan: Blue Streak & Blue Streak Steroid (both rockers) / AA TX200HC

NorthStaR

What kinda numbers are people pumping out in .22 with these valves? Any takers?
Double-tap!

Crosman: Western 45, Western Shiloh 1861, 766, *Mk1*, 2250b Crosmods, AS2250XT Quickshot Repeater, 2240 Bling Star,
                1322 Folding Camo Sniper, Bling EB22, 2250b Violin TDR, W-2250, Crosshairs Special 1377SD, 2550 Carbine & still counting...


In progress: BNM BSA 2260 Repeater, SS Subcompact Stubby 22xx, 2 x 600, and .... and ....

tayloriand

#19
.............. AGAIN !!!!!!!!!!!!

Well chaps, all I've done with my first 1377 is put a lighter trigger spring in it and I've bought a second 1377 ! Should be with me in a few days.

This one is bone stock again but supplied with a GMAC FT Piston and valve NOT fitted yet.

Has anyone bought one? The GMAC website only describe the product as:
"1377 Flat Top Piston Kit will fit the 1322 1377 2289 1389 7 pumps will do the same as 10 pumps with the standard setup"

Question is do the valves from GMAC, Meon, AC have angled valve, lighter valve spring, etc or do they only machine the valve face

Cheers
Ian

member of Dukinfield Air Gun Club
www.dukinfieldairgunclub.webeden.co.uk
Undercover 30 lanes up to 35 yards including 5 pistol lanes
Paper, knockdown targets, spinners, etc

1377x

ac machines the valve face he'll port it if requested ,he uses the stock vave spring but mods the check valve iirc the port is angled
http://accustomparts.com/13xxvalve.aspx
closed mouths dont get fed