More plinkster malfunctions

[DenverGP]

well, put another 600 rounds or so thru the Plinkster with no issues. Cleaned it after the last range trip, and this time out it had a bunch of problems.

Had some failure to feed, where the round seemed to get hung up on the feed ramps. Usually dropping the mag, locking the bolt back, clear the round, and reinsert the mag and let the bolt close would correctly chamber the next round. I'm wondering if the mag spring is weak, not holding the round up strong enough to chamber cleanly.

Also had a few failure to ejects, where the round seemed stuck in the bore. With the rifle disassembled, I inserted a round into the bore, and slid the bolt forward against the round, and could see the extractor fit around the round, but wouldn't always hold tight enough to actually pull the round out. So wondering if the extractor spring is too weak, or if the round is too tight in the bore...

Seems odd that both issues started all at once after a couple flawless days shooting and a good cleaning.

How loosely should a round drop into the bore? I hadn't tried it before, but while troubleshooting with it all disassembled, I manually inserted round into the bore, and it's a rather tight fit, much tighter than on my pistols.

 

[mingaa]

Basic question but were you using the same ammo throughout? The 702 is not known to be overly sensitive to ammo types as long as it is LR with enough power to cycle the gun. Guns do differ on a gun to gun basis.

What ammo were you shooting?

 

[DenverGP]

It's the exact same ammo i've been shooting, a mix of CCI Mini mag, federal auto-match and some federal 36gr copper plated.

Also, I didn't make it clear on the first post, the failure to feed happened on the first round (when releasing the bolt on a newly inserted full mag) as well as happening in the middle of a magazine when cycling.

My main thought is that maybe the magazine spring got a little bound up or something, and it wasn't feeding correctly. I plan on getting a couple new mags, we'll see if that resolves the feeding issue.

I'm more worried about the FTE issues, where the extractor doesn't even pull the round out of the chamber. The extractor isn't binding up, I cleaned it well and lubed it well, but manually cycling the rifle, the bolt will not pull an unfired round back out of the chamber.

The hook on the extractor seems fine, but i'm wondering if maybe it got bent a little bit.

 

[DenverGP]

I'd like to hear from anyone else if the 22 round should drop right into the chamber, or if it's supposed to be a tight fit. On mine, if I try to manually insert a round, it's real tight fit, I have to push it in, and then it won't drop back out, even unfired. I had to use a knife or screwdriver to remove a round from the chamber.

 

[DenverGP]

well, disassembled the rifle and removed the barrel and found the issue. I could see a little burr right where the striker would hit. A little bit of careful work with some small files, a 22 round drops right in, and the gun is running smoothly now. I had some issues with the magazine not feeding smoothly last time out, so I'm guessing it caused some dry fires.

 

[mingaa]

Glad you figured that out - tough to diagnose until you tear it down and crawl through it. Which mag gave you trouble 10 or 25?

 

[DenverGP]

was with the 10 rounder, seems like the spring isn't as strong as it should be, not pushing the follower up to keep the round angled correctly.

Just ordered up a new one from Cabellas. $22, a little high, but free ship-to-store and they had them in stock.

 

[BowerR64]

WHen you clean the gun dont forget to clean that mag also. .22 is a dirty round and right where the mag sits gets alot of fouling and it can fall right into the mag.

WHen i clean my mags i run some fine sand paper around the spring then push a wadded up paper towel um into the mag then back out then i oil it.

Even though the spring is a round wire it can still get burs on it also. You will find brass shavings, chunks of unburnt powder and kinds of crud in mags.

If your not hungin with your semi autos try and chose a solid point ammo.

Have you thought about polishign the feed ramp? You can use a fine grit sand paper 800-1200 and a pencil eraser and just rub the feed ramp till its really smooth. This helps not only feeding but the smoother the feedramp is the less fouling hangs on it causing binding and feeding issues.