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Tuning Umarex M1A1 Thompson Repair

I have some silicone spray. When I receive the gun do I remove the clip and just the slide? Anything else to lube?
Also I have half a bottle of Crossman Copperhead BBs. Any issues with these?
100% silicone oil or spray. Sure spray the head of the clip and where the clip is inserted.
WD 40 makes a inexpensive but it leaves a "gunk" behind; 100% silicone spray called "WD-40 Specialist- 100% Silicone Spray". But be ware it comes out like a firehose. About $7 dollars a for an 11 oz can which is pretty cheap. I just squirt out the can is a tall plastic container and let sit sit for 24 hours to de-gas the silicone oil and presto! put it is any small container.

Are the Copperhead BBs Premium BBs or do they have the little dimples ln them?
I recommend only manufactured Premium BBs. Steel Zink or Nickle coated BBs (silver in color).
 
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I got myself one for Christmas.
I am glad you took the time to post and explain,it helps knowing what's up.
Years a ago I had a Mattel Tommy gun,it really help me feel safer when I was 7 years old and watched "Frankenstein Meets the Werewolf" by myself.I was truly scared,but was engrossed with the movie.
Nowaday I have my custom .45 next to me when I watch the news.:p
 
I got myself one for Christmas.
I am glad you took the time to post and explain,it helps knowing what's up.
Years a ago I had a Mattel Tommy gun,it really help me feel safer when I was 7 years old and watched "Frankenstein Meets the Werewolf" by myself.I was truly scared,but was engrossed with the movie.
Nowaday I have my custom .45 next to me when I watch the news.:p
 
Well do not give it a bath!
Spray the clip head a spray into the the magazine chamber. Also the sear lever where it is attached to the barrel in the front, it is the metal bar above the bolt return. I would also spray into the magazine BB spring chamber (that holds the 30 BBs). When and if you separate the upper from the lower spray the entire inside of the M1A1 too much of investment not to.

With that you should not have any problems with the copperhead BBs, except with the M3 Grease Gun SMG; man that thing is particular what BBs it will use! Only Premium Steel BBs work in that M3 Grease gun.
You should not have any problems.
picture below is the correct way the sear connects to the bolt (the bolt is the top housing of the M1A1).

Sear on top of bolt catch.jpg
 
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Great.
If by chance the you find yourself having to operate the bolt because it seems jammed after several clip BB reloads; give another drop of oil in the clip tip (both ends) and a couple drops in the BB channel in the clip.
Other than that Happy shooting!
I was searching for bb jams when co2 capsules are about to drain. To my surprise I stumbled on your detailed field stripping post and that's some serious high quality analysis!
I have to register an account to let you know my thankfulness.
 
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I too have a rifle made by Umarex, it has a compression chamber made from what appears to my eye...pot metal, the barrel lock has broken from the front of the chamber. Umarex won't sell parts to fix it so I'm going to strip it down, clean it up and try an silver solder it. If it holds great if not it's going into the dumpster. I've tried to contact a couple of people that was suggested to me.... but no response, the rifle could be replaced with new for less than it would cost to ship it to and from a repair shop anyway. I wish you well with yours, it was an interesting read too so thank you for that.
 
I too have a rifle made by Umarex, it has a compression chamber made from what appears to my eye...pot metal, the barrel lock has broken from the front of the chamber. Umarex won't sell parts to fix it so I'm going to strip it down, clean it up and try an silver solder it. If it holds great if not it's going into the dumpster. I've tried to contact a couple of people that was suggested to me.... but no response, the rifle could be replaced with new for less than it would cost to ship it to and from a repair shop anyway. I wish you well with yours, it was an interesting read too so thank you for that.
Do you have pictures of the damage?