please school me on short cycling

[garandtom]

Hello fellas! I just recently got a new op-rod and spring from a Marine friend of mine and now my rifle shorts cycles on rounds 5-8 consistantly. What causes this? I also installed a ported gas plug. The rifle functioned flawlessly before the rod and spring got replaced. could my gas cylinder be out of spec or worn out?

[Orlando]

Is the Op Rod your friend in spec? What the piston measure?
What brand of Op Rod spring are you using? Wolff extra power springs can cause short stroking on some ammo.
What brand gas screw are you using and did it function before with the ported screw? Is gas screw tight?
Short stroking can be caused by a number of things but since these two things you changed and it functioned before I would look at them first

[Prince Humperdink]

Perhaps the rod bend is not correct for your rifle and is rubbing?Did You tilt test it?And all Bill mentioned :)

[REHRIFLE]

It seems strange that this only happens on rounds 5-8.

Bad op rod and spirng would cause short stroke through out the clip.

[garandtom]

He replaced my gas cylinder due to being out of of spec and worn out. She fires without a problem!

[Mike]

Hello fellas! I just recently got a new op-rod and spring from a Marine friend of mine and now my rifle shorts cycles on rounds 5-8 consistantly. What causes this? I also installed a ported gas plug. The rifle functioned flawlessly before the rod and spring got replaced. could my gas cylinder be out of spec or worn out?
Hi, I'm glad you have your problem fixed. My question is if your rifle "functioned flawlessly before the rod and spring got replaced"; Why did you replace it?
When I was new to Garands I had a "Gunsmith" replace my WWII GI parts with "other" parts. Regards, Mike

[garandtom]

Mike- My spring was worn out and my op-rod was bent so he replaced them. he also said the piston was out of round. He forgot to gauge the gas cylinder when he replaced the spring\rod.