CROSMAN 1377 ISSUE

[ironsights]

my 1377 newer version, just started to go off while I was pumping, I cock it, insert pellet, pump 5 times, it shoots out pellet at a low pressure while pumping, happens at the 5th pump. Safety is on too. I've never pumped it more than 8 times. Bought it just 2 weeks ago at a canadian tire. Less than 300pellets shot. 
What could be wrong? accuracy is amazing, simple and fun to shoot.

[happymecanic]

How old is your newer version 1377? Is it made in U.S.A. with ''globally sourced parts'', or maybe made in China?

My guess is too loose machining tolerances, when it starts to have a certain amount of pressure the gun sorta ''twist'' and allows the sear to let go. I may be wrong though.

Have you tried not cocking before pumping? If so, what happens?

Have you checked if all the screws are tight?

[ironsights]

it says 1377 classic on the box. all black color including bolt. the foregrip has the deep groove on each side. Made in China on metal frame

Tested it BY pumping first, safety on, then cocking. Its ok. I was told to cock first then pump, it's safer and better for these guns. 

How old is your newer version 1377? Is it made in U.S.A. with ''globally sourced parts'', or maybe made in China?

My guess is too loose machining tolerances, when it starts to have a certain amount of pressure the gun sorta ''twist'' and allows the sear to let go. I may be wrong though.

Have you tried not cocking before pumping? If so, what happens?

Have you checked if all the screws are tight?

[BerkshireHunter]

Well obviously, be careful about loading it and handling it... I dont' think I've ever heard of one going off that easily. Now if you had polished the trigger and reduced the spring tensions, it might be a "light trigger" to be cognizant of.
But a new gun going off just pumping? Yeah, sounds like the hammer is slipping way too easy. I would suggest taking off the grip frame panel to look at the setup, maybe the sear is defective or a part is broken?
I'm sure calling Crosman would work too but I wouldn't be surprised if the issue becomes apparent upon a rudimentary disassembly.