Crosman 1377 Modding

[Biker_Bob]

Done a few mods.
Crosman Steel breech
PAO 2X20 scope
2240 silencer adaptor, shaved in the milling machine so it clears the pump tube - the barrel is free floating now.
Stainless pump pivot.
Aluminium extended pump handle - these pistols are so hard to pump using the standard pump handle when a scope is fitted.
Aluminium shoulder stock adaptor - in the photo there is a stabiliser / counterweight fitted, this counters the forward heavy feeling when the silencer is attached. I've also made a rod stock that fits in instead, it has an unusually long reach but it allows me to use the pistol scope in rifle mode, I'm quite tall so it feels fine for me.
PLA+ 3D printed target grip with adjustable palm shelf.

Full power valve mod, now running 5.7 ftlbs with JSB 8.44gn
Pellet on pellet at 15yds with the shoulder stock fitted.

https://flic.kr/p/2niVBC1

[ratbuster2240]

Nice build! A standard one always surprises me with it's accuracy, so this must shoot very nicely.

[rapidboy1]

Nice work, that grip looks great.

[Biker_Bob]

I can't claim credit for the grip - I found it on a Russian 3D model sharing site. I did make a quick modification to correct the gap between the grip and palm shelf which was too wide, but that's all.
I've also printed out some 5 shot magazines, they're manual indexing and clip onto a holder that sits in the dovetails on the steel breach - they work really well and save a lot of faffing trying to get the pellets in, especially with the scope fitted, which restricts access.
I also forgot to mention that I fitted a Droid slot head screw re-bolt kit, which replaces all the horrible tiny allen keyed screws that the 1377 is blighted with and the safety is missing because that pigging tiny ball shot off when I was trying to reassemble. Mr Droid came to the rescue again with a pack of three balls and screws - but I have yet to fit one.

[ratbuster2240]

Those tiny ball bearings get everywhere. It's worth buying a 100 pack for a few quid.

[Biker_Bob]

They are little beggars.
I still haven't figured out the best way to fit them, usually I end up juggling with a knife and a flat blade screwdriver and half of the time they just shoot off anyway.

[rapidboy1]

You should sell the grips, loads of aftermarket grips available but target style grips are few and far between.
A little blob of grease on the spring and the ball bearing sticks to it ....
Are you running a flat top piston ?

[--ped--]

everyone looses a safety ball and spring and i have a bag of each on my bench as many guns i get haven't them fitted
one tip to avoid them flying off is to not remove the trigger side plate whilst the frame is on the gun and as above a dab of grease helps keep them from just dropping out

[Biker_Bob]

Blob of grease it is then - I'll give it a go - thanks!

I'm not getting into selling grips, it took 23 hours to print with the palm shelf and since it's not my design I think it would be legally dodgy.
If anyone wants to print their own (or get one printed) I can point them in the direction of the site to download the files.

[Adam77K]

Blob of grease it is then - I'll give it a go - thanks!

I'm not getting into selling grips, it took 23 hours to print with the palm shelf and since it's not my design I think it would be legally dodgy.
If anyone wants to print their own (or get one printed) I can point them in the direction of the site to download the files.

Regards the legal point, it depends on the licence provided with the files on the site. I don't know which site but for example if it was Thingiverse it will be one of the Creative Commons licences and as long as it wasn't under one of the Non-commercial variants you'd be ok to sell the items.
https://www.3dprintingspot.com/post/...om-thingiverse

[Biker_Bob]

Regards the legal point, it depends on the licence provided with the files on the site. I don't know which site but for example if it was Thingiverse it will be one of the Creative Commons licences and as long as it wasn't under one of the Non-commercial variants you'd be ok to sell the items.
https://www.3dprintingspot.com/post/...om-thingiverse

It was all in Russian - I did my best with Google Translate, but it was all I could do to create an account and download the files!

[Biker_Bob]

You should sell the grips, loads of aftermarket grips available but target style grips are few and far between.
A little blob of grease on the spring and the ball bearing sticks to it ....
Are you running a flat top piston ?

What does a flat top piston do?
It's running as high as I want it to run power-wise with the standard set-up.

[rapidboy1]

What does a flat top piston do?
It's running as high as I want it to run power-wise with the standard set-up.

Saves a bit of pumping, 6 pumps with FTP is supposed to be the same as 10 pumps with the regular set up.

[Biker_Bob]

Saves a bit of pumping, 6 pumps with FTP is supposed to be the same as 10 pumps with the regular set up.

OK, but what happens if you put 10 pumps in with FTP?

[rapidboy1]

Depends on how you set it up