Refurbing an old 1377

[Somnophore]

I'm looking to learn a lot about these pistols and I thought refurbing and customising my old 1377 might help me do that without breaking open a brand new 1377 and risking mucking it up.

I know I can't convert it to a new style 1377 as it will have to retain the cocking knob but I've read I can but a steel breech in but that it just won't cock the gun.

What I am thinking of doing is learning about the internals and renewing some of them, I don't know if to just to replace seals on the existing piston/valve or to upgrade to flat top.

My main priority is to make sure the power is up to scratch as its a 1995 model so may be in need of some work.

Second it's to improve accuracy so I want to swap out the smooth bore barrel for a rifled one off the new 1377c.

What else would you advise? It's mainly a plinking and hunting pistol, I actually like the idea that I can have the gun charged and loaded but not cocked, it's safer but will be ready to use when a squirrel pops up on my bird feeder. Also the little bit between tube and barrel is the transfer port yeah? On YouTube I've seen video saying one side is bigger than the other, on mine it seems to be same size either side.

[cmj21973]

The older 13xx guns had transfer sleeves that were same on both ends and the barrels had smaller ports with squared (end milled) counter bored ports.
The 13xx's that have the bolt action breech have the newer (long end / short end) transfer sleeve and the barrel ports are larger, non squared counter bored ports.

Power should be the same. Your valve should be brass which is better than the aluminium valve that are in the newer guns.

[Somnophore]

So would you keep the original piston/value and just renew the seals or would you go flat top? What's the benefit of flat top, I've heard I can get full power with only 7 pumps. It's seems to shoot ok power wise but I don't have a chrono, but with the age of it and if in going to work on it it's worth at least renewing the seals before I mod anything else.

I don't know what's best to be honest, also to disassemble the gun do I need special tools, the cocking arm that's attached to the pistol is pinned in by the look of it. My worry is ill break something trying to get it apart or won't be able to get it back together once it's apart lol.

[arkmaker †]

You will need a punch to take out the arm. But then I would replace that roll pin with a solid pin, so that taking the pump arm on and off in the future will be much easier and less chance to be smacking your tube with the punch.


IMHO: I would just do the reseal on an older pistol and keep it original. Buy a new one to mod. But then again, that's just me. It's fun either way!!

[cmj21973]

The first mod to any 13xx should be the solid pin mod. This make future disassembly a lot easier.
They can be bought or you can make your own.
The older phase I 13xx had a solid with a e-clip on them. The phase II and current guns have a rolled pin.

The roll pin can be knocked out with the right size punch or you can grind the point off of a nail, that's about the same size as the pin.
Knock the pin out from right to left,  from shooter's perspective.

[YSYEO]

Regarding removing/installing the pivot roll pin.   If you have a punch or flattened-tip nail AND you also have a drill press, then you have a makeshift arbor press that I find much easier to use than tapping with a hammer.

I have a block of plastic with a hole that I use to support the tube and catch the pin.  I put the punch in the drill chuck (and if I want to be safe I unplug the drill press).   This lets you remove the pin with no tapping.   

To replace the pin, I tap it lightly with a hammer to get it started, and then press it the rest of the way.

That said, I do have a solid pin on order for my 1322c.

[1377x]

the old 1377's can be modded just like the new ones but with better performance give the hammer spring isnt weakened even then a thick washer with a slot cut out of it will add some preload to it hopefully bringing it back and beyeond spec
heres my phase with all the current mods i use the pull knob to charge the gun much better than the bolt style

[johnhl]

The first mod to any 13xx should be the solid pin mod. This make future disassembly a lot easier.
They can be bought or you can make your own.
The older phase I 13xx had a solid with a e-clip on them. The phase II and current guns have a rolled pin.

The roll pin can be knocked out with the right size punch or you can grind the point off of a nail, that's about the same size as the pin.
Knock the pin out from right to left,  from shooter's perspective.

Looking at my 1377 and the Crosman EVP for the same model, it appears that the pivot pin and the pump handle pins are driven IN from right to left from the shooter's perspective (that means with the muzzle pointed away from you, I assume). Wouldn't that indicate that the pins are driven out from left to right? Or am I missing something? Thanks. John.

[1377x]

my phase 2 1377 came with a solid pin with clip i changed it out to a mellon pin because it looks much better. but on my phase1 1377 i used the ring for the pump lever on it and the solid pin in another 1377

[JEBert]

Looking at my 1377 and the Crosman EVP for the same model, it appears that the pivot pin and the pump handle pins are driven IN from right to left from the shooter's perspective (that means with the muzzle pointed away from you, I assume). Wouldn't that indicate that the pins are driven out from left to right? Or am I missing something? Thanks. John.

John,
Your observation of the EVP raises an interesting question.  The pins and sights into dovetails in all other guns I have worked on or heard anything about, go in from left to right and out from right to left.  I would assume that Crosman adheres to these standards but I could be wrong.  The diagrams I have of some other guns do not necessarily reflect the direction that the pins and sights are installed.
Who knows for sure?
Cheers,

[BDS]

yes, assembly diagrams do not (necessarily) show the orientation or direction of a part except by the artwork or picture, those lines from a fastener or pin to it's home position simply show where it goes in the assy.

[johnhl]

yes, assembly diagrams do not (necessarily) show the orientation or direction of a part except by the artwork or picture, those lines from a fastener or pin to it's home position simply show where it goes in the assy.

I'm inclined to agree, Brian. My reference to the EVP was more of a clue than a conclusion. However, the EVP notwithstanding, my particular 1377 (purchased new by me) appears to have  the pins pressed in from R to L. Under a little magnification, I can see the pivot pin is concave (or dished in) on the right and flat on the left. Also, on the plastic pump handle, there is a small crescent dimple at the periphery of each pin hole on the right side and plastic shavings in the holes on the left side. Those indications would seem to be consistent with the pins being pressed in R to L (imho). As long as there is a satisfactory outcome, I'm sure there is no wrong way to do it. I'm just looking for the easiest. And that's usually the way the manufacturer does it.

[markasaurus]

I actually like the idea that I can have the gun charged and loaded but not cocked, it's safer but will be ready to use when a squirrel pops up on my bird feeder.

Actually that's no problem with a modern 13xx either.  All you have to do is de-cock it.  You just grab on the bolt, pul it back, hold it back, pull the trigger and ease the bolt and hammer forward. 

[1377x]

Actually that's no problem with a modern 13xx either.  All you have to do is de-cock it.  You just grab on the bolt, pul it back, hold it back, pull the trigger and ease the bolt and hammer forward. 

yeah but with a phase 2 you dont have to decock it   just cock it when ready

[Somnophore]

I've seen someone shoot themselves I'm the foot trying to decock and air rifle before :s