Pump mag issues

Biscuit · 06-28-2011, 10:49 PM

Alright, so I just recently threw together a pumpmag. One big problem. It is a pain to cock. The stroke is smooth as could be, but when it actually comes to pushing the bolt back onto the sear it becomes a real task. Also, it takes the ENTIRE pump stroke to cock it. Like the return spring is smashed together when the sear catches. Any ideas?

b-cuzz · 06-28-2011, 11:05 PM

Never messed with one, but is your pump rod too short? If it's adjustable, you might back it out a few turns and see if that helps.

weekendballer · 06-28-2011, 11:09 PM

bumper behind the bolt to thick?

Biscuit · 06-28-2011, 11:14 PM

Sanded down the bumper a good bit. That helped a very small amount. Honestly, it just made it so that it could for sure be pumped every time. I have back out the rod and that didn't help a ton either. Main spring is also unclipped.

senghing27 · 06-28-2011, 11:38 PM

Classic valve, stock mainspring, wavespring, flipped oring/carrier within powertube, bolt is clean, rod isn't binding/getting caught?

Should be able to do what I can in my video

Pictures of your setup?

Biscuit · 06-28-2011, 11:43 PM

I'll get pics tomorrow. Maybe I missed a step, what do you mean by "flipped oring/carrier"?

senghing27 · 06-28-2011, 11:45 PM

Quote:

Originally Posted by Biscuit

I'll get pics tomorrow. Maybe I missed a step, what do you mean by "flipped oring/carrier"?

Within the powertube, you swap the carrier and the oring when you run a pump mag. No necessary, but I find it to be a nice touch.

You might need to clip your mainspring, it may be too strong.

Biscuit · 06-28-2011, 11:55 PM

Not that I think your wrong, but how would clipping the mainspring make the stroke lighter

senghing27 · 06-29-2011, 12:00 AM

Quote:

Originally Posted by Biscuit

Not that I think your wrong, but how would clipping the mainspring make the stroke lighter

It's for a different purpose, I figured while we're trying to diagnose problems, take care of usual ones.

Pump stroke could be several things as of right now.

People tend to wear out their wavesprings really quick because of the mainspring being too strong (completely separate thing tho).

Now that I think about it, is your bumped sized with the wavespring?

Double check and make sure everything looks kosher to this
http://haveblue.org/tech/automag/index.html

Biscuit · 06-29-2011, 12:10 AM

haveblue isn't wanting to load for me right now. Though, I figure I should have mentioned this earlier, I am still running the green stock bumper. I have seen people talking about putting the bumper IN the wavespring? I don't really see how that would work, but maybe you have some insight. If I try just the wavespring the pump arm does not reach the bolt.

06-28-2011, 10:49 PM	#1 (permalink)
Biscuit Rec Poster Join Date: Nov 2008	Pump mag issues Alright, so I just recently threw together a pumpmag. One big problem. It is a pain to cock. The stroke is smooth as could be, but when it actually comes to pushing the bolt back onto the sear it becomes a real task. Also, it takes the ENTIRE pump stroke to cock it. Like the return spring is smashed together when the sear catches. Any ideas?

06-28-2011, 11:05 PM	#2 (permalink)
b-cuzz MCB Member Join Date: Feb 2008 Location: Nevada, Missouri	Never messed with one, but is your pump rod too short? If it's adjustable, you might back it out a few turns and see if that helps. __________________ Worm 4 insists it's personal. "Our doubts are traitors, and make us lose the good we oft might win, by fearing to attempt". -William Shakespeare My feedback: http://www.mcarterbrown.com/forums/f...-feedback.html My weapons: http://www.mcarterbrown.com/gallery/...rsenal&cat=500

06-28-2011, 11:09 PM	#3 (permalink)
weekendballer MCB Member Join Date: Mar 2007 Location: Detroit MI	bumper behind the bolt to thick? __________________ FEEDBACK T-Shirt Hell Pumps for sale Prostocks for sale

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06-28-2011, 11:14 PM	#4 (permalink)
Biscuit Rec Poster Join Date: Nov 2008	Sanded down the bumper a good bit. That helped a very small amount. Honestly, it just made it so that it could for sure be pumped every time. I have back out the rod and that didn't help a ton either. Main spring is also unclipped.

06-28-2011, 11:43 PM	#6 (permalink)
Biscuit Rec Poster Join Date: Nov 2008	I'll get pics tomorrow. Maybe I missed a step, what do you mean by "flipped oring/carrier"?

06-28-2011, 11:55 PM	#8 (permalink)
Biscuit Rec Poster Join Date: Nov 2008	Not that I think your wrong, but how would clipping the mainspring make the stroke lighter

06-29-2011, 12:10 AM	#10 (permalink)
Biscuit Rec Poster Join Date: Nov 2008	haveblue isn't wanting to load for me right now. Though, I figure I should have mentioned this earlier, I am still running the green stock bumper. I have seen people talking about putting the bumper IN the wavespring? I don't really see how that would work, but maybe you have some insight. If I try just the wavespring the pump arm does not reach the bolt.