Hard trigger pull on ar15

[Grimreefer]

Hey fellars

I have a 223 colt sp1 . Shoots great if you slow fire the weapon but if you get into about a 15 to 30 rounds back to back quick firing the trigger becomes very stiff can hardly pull it back after 20th rounds. So my lack of understanding the weapon prevents me from diagnosing the problem

 

[BADUNAME37]

Are you aware if it is the OEM trigger that came with the gun new? I've seen problems related to certain trigger pins being in receiver-drilled left and right holes that are not quite exactly lined up with each other (side to side). That resulted in a bit of binding of one or both of the trigger pins that you see on the left and right sides of the receiver. If something is wrong, similar to what I am stating, then the gun heats up, things that were not binding when the gun was not yet shot may start to bind upon the expansion of certain components due to heat.

 

[rcmodel]

Have you tried oiling the trigger & hammer pins?

Also pop it open and shake it.
There may be a spent primer or a bird nest in there!

rc

 

[Grimreefer]

Thanks remodel $ FDF

No I'm not sure about the type of trigger in the rifle it was my fatheriaws and he passed some years ago . It does sound like your on the right Track with the
HeAting up and expansion that comes from the heat . But yea your right rcmodel a little oil wouldnt hurt either ! Lol. If it is the misalignment of the holes as you were talking about FDF. What can be done?

 

[rcmodel]

It is very very unlikely a Colt SP-1 got out of the Colt factory with out of spec holes.
Not to say some Bubba didn't jack up the trigger, sear or springs later!

Colt SP-1's were all built to the same Mil-Spec standards as the Colt M-16 USGI service rifles of the time.

They were either right, or they didn't get past the Q-check inspections & gages.


Do you know how to open it and clean & oil it?

If not, go here for take-down instructions:
http://www.ar15.com/forums/t_3_7/456002_Field_stripping_the_AR15__massive_pics_.html

Here for Lube instructions:
http://www.ar15.com/forums/t_3_7/548967_AR15_LUBE_POINTS.html

rc