Crosman 600 feed issue

[shibumei]

Thought I would just run this by and see if any insight offered.  I have a 600 that was shot very little and almost pristine so I doubt if any wear and tear issues.  It leaked, so I resealed  and all is good.  I know this model is extremely pellet picky with wad cutters almost exclusively recommended.  But why (I've read) do so many 600's feed domes flawlessly?  I see no way to adjust pellet feed to compensate in any way.   This particular gun is fist variant so just FYI. The gun shoots anything I've tried when only a single pellet in the magazine but jams eventually with multiple of any type.  I have not tried wad cutter yet. I've ordered wad cutters of different types to see if resolves but why such a discrepancy between guns and jamming issues?  Feed arm is perfectly aligned with magazine.  I'm head scratching

[Matchstickshooter]

Just my 2 cents here, but I had read that the 600 feeding problems was why Crosman starting adding something to the lead to harden it a bit.
 Believe the ingredient was called Antimony.
 Softer lead pellets not so good.

[WyoMan]

Hi Garry,

Here’s why…
The feed arm is wide enough that the next pellet in queue can get its nose in, slightly. It has to be that way so the pellet getting fired won’t get its skirt snagged on the frame. You can’t get the tolerances tight enough (pellets aren’t perfectly uniform) to have it any other way.

When the feed arm loads (moves down to fire) it will actually push the pellet magazine stack to the rear.

See the excellent video by jacksmirkingrevenge in this thread:
https://www.gatewaytoairguns.org/GTA/index.php?topic=151393.msg1552829#msg1552829

He’s using domes and they will “nest” into the pellet skirts.

Here’s a stack of wadcutters:


Here’s a stack of domes:


Even though the individual domed pellets are 10 thou longer, their 10 pellet stack is 3/16” shorter. So the feed arm action has to push the stack further back with domes… and sometimes it can’t. Could be binding in the magazine, rough spots, misaligned/skewed pellets, magazine follower or spring, weak cam action at the start of rotation….Too difficult to diagnose.

But there’s one easy thing to try,,, smooth the feed arm where the next pellet will make contact (when it’s pushed back):


But your problem should be solved with wadcutters. If not, let us know…
One more thing, make sure you slowly release the follower and it doesn't slam into the pellet stack - that will cause jams/mis-feeds almost every time.

Wyo

[shibumei]

Thanks so much for the feed back.  I think I have resolution.  At least for the wad cutter.  Received first wad cutter in mail today as cheapo .22 Cal H&N EXCITE plinking.  And as luck would have it, they jammed also on first attempts same as with domes.  This is what I did and now these pellets seem to cycle pretty well. No jams yet.  I loaded a single pellet into the magazine and also one into the feed arm. The pellet in the magazine was under spring tension.  With no C02 in gun, I loosened the feed arm screws to the cam and  cocked gun and then held trigger down while slowly releasing the slide to cycle the motions until no drag was felt with pellet in feed arm and pellet in magazine.  There is definitely a sweet spot in that cam dimple.  Tightened down the set screws and loaded a c02.  Shot twenty pellets perfectly.  Then I loaded with Crosman ultra mag domes and new c02.  Fired off about 6 and then a jam.  Grrrrrr!  At least some progress.....   

[WyoMan]

Well I blew that diagnosis, lol.... but it's nice to hear you have it sorted. I use wadcutters in all of mine. The domes can sort-of work but not nearly as reliable. I suppose if you only wanted to load about 4 or 5... but a full stack of ten takes more of a beating from the push-back, push-forward action. And by the time you're near the end, the nesting gets much worse. Also the follower push from the spring is greater when the mag is fully loaded.

You're right about trying to get that bottom setscrew in the bottom of the recess (dimple). They will not self-align and tend to "set" when they hit a side instead of the bottom. This of course means that the feed arm will work its way loose from the cam. But good job in finding the fix!

Wyo