Tuning Umarex M1A1 Thompson Repair
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So here we are. The project is complete the new wood furniture (grips and stock) have been fitted and installed. Three coats of dark Walnut stain and 3 coats of Polyurethane (man that took a week Stain 8 hours to dry/cure, polyurethane 6 hours to harden/dry. I do have a life outside of this project.
I wish to note that from the beginning I made the decision NOT to modify anything on the UMAREX M1A1 Thompson BB gun. I always wanted to return the M1A1 back to original factory at anytime of my choosing. I also did NOT want to use any of the hardware on the UMAREX M1A1 for the King Arms wood stocks. All of the bolt holes and the main fitting in the stock had to be changed.
Let us start talking about bolts.
I knew from the beginning that the bolts/screws were metric, Thank the lord there was a panel on the WALL of bolts there was a panel in the hardware store to fit match/metric screws. The screws are all M6-1.00 machine bolts for foregrip, pistol grip and two bolts for the stock I chose the better round phillips machine screws, the flat headed screws... well I just do not like them and more difficult to remove. The stock where the two metal disks attached to the M1A1 stock on both sides is an M5-8.0 60mm. The length of the bolt are measured in mm. I will list them for you later.
Lets start with the foregrip. This was the easiest one to do. The wood and plastic parts were the same size obviously both companies modeled their grips to match the original WWII M1A1 furniture. Pictures below show how I matched and drilled new holes and countersunk the bolt holes. I then plugged The Airsoft holes with wooden pegs/dowels. I did not want an extra hole in the foregrip.
Just pictures for now; I am changing to a new video editor so no videos for now. I aligned the UMAREX with the woos King Arms foregrip drilled the hole countersunk the outside hole and test screwed in the M6-1.00 25mm bolt. I thought to myself "Wow, that was easy." I did not care about the finish as I planned on doing that later when I had all of the furniture fitted.
That is it for now, like I wrote I do have a life... next stop the Pistol Grip.
Just a note: The new bolt hole is not finished so it looks rough, it will be finished and look great.
I wish to note that from the beginning I made the decision NOT to modify anything on the UMAREX M1A1 Thompson BB gun. I always wanted to return the M1A1 back to original factory at anytime of my choosing. I also did NOT want to use any of the hardware on the UMAREX M1A1 for the King Arms wood stocks. All of the bolt holes and the main fitting in the stock had to be changed.
Let us start talking about bolts.
I knew from the beginning that the bolts/screws were metric, Thank the lord there was a panel on the WALL of bolts there was a panel in the hardware store to fit match/metric screws. The screws are all M6-1.00 machine bolts for foregrip, pistol grip and two bolts for the stock I chose the better round phillips machine screws, the flat headed screws... well I just do not like them and more difficult to remove. The stock where the two metal disks attached to the M1A1 stock on both sides is an M5-8.0 60mm. The length of the bolt are measured in mm. I will list them for you later.
Lets start with the foregrip. This was the easiest one to do. The wood and plastic parts were the same size obviously both companies modeled their grips to match the original WWII M1A1 furniture. Pictures below show how I matched and drilled new holes and countersunk the bolt holes. I then plugged The Airsoft holes with wooden pegs/dowels. I did not want an extra hole in the foregrip.
Just pictures for now; I am changing to a new video editor so no videos for now. I aligned the UMAREX with the woos King Arms foregrip drilled the hole countersunk the outside hole and test screwed in the M6-1.00 25mm bolt. I thought to myself "Wow, that was easy." I did not care about the finish as I planned on doing that later when I had all of the furniture fitted.
That is it for now, like I wrote I do have a life... next stop the Pistol Grip.
Just a note: The new bolt hole is not finished so it looks rough, it will be finished and look great.
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I almost forgot; the wooden dowels the plug the hole. Fit a wooden plug in the old hole a little Elmer's glue and overnight cut off the excess sand it down and done.
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I promised to reveal all so here are the costs of the wood grips below.
When I got the wood grips 8 days later (pretty fast actually) I noticed that the sling attachments were not included; which kind of surprised me.
I didn't want to use the UMAREX Sling hardware (dot not fit anyway). So I had to order the sling hardware separately. So if anyone decides to go the wood upgrade route order the sling hardware when you order the wood furniture.
Vendor King Arms (TaiwanGun Team)
Country of Origin- Poland-
Pollanki 18/B 30-740
Krakow, Poland
M1A1 Wood Conversion Kit [King Arms] 3 pcs $110.19
Delivery Method UPS Express Saver Courier Delivery $39.00
Total amount $149.19
Assembly Sling Attachment points on fore grip and stock.
V Production International Company Limited
(Country of Origen) Taiwan
Address: No. 321 Hsi Nann Road See1, Wurih Dist,
Taichung City, Taiwan 41465
AS-M79P-06-A01 2 ea. $10.00
SCR-ST-3M5x16Z-A01 4 ea. (Screws) $4.00
Shipping Cost Shipping $22.00
Bank fees $1.80
Total Amount $37.80
Total Costs $186.99
So now you have full disclosure of the costs and shipping. All the parts came very quickly (my opinion) and after ordering arrived swiftly. The wood furniture came in a cardboard box with KING ARMS Logo large sticker on the box end and the wood furniture was wrapped with bubble wrap individual bags and with a darker stain than the UMAREX paint/color. The king Arms finnish on the wood I can only describe as a strong Plastic coating (not polyurethane or varnish) finish.
I intended from the start to refinish the furniture when I was done with the fitting.
When I got the wood grips 8 days later (pretty fast actually) I noticed that the sling attachments were not included; which kind of surprised me.
I didn't want to use the UMAREX Sling hardware (dot not fit anyway). So I had to order the sling hardware separately. So if anyone decides to go the wood upgrade route order the sling hardware when you order the wood furniture.
Vendor King Arms (TaiwanGun Team)
Country of Origin- Poland-
Pollanki 18/B 30-740
Krakow, Poland
M1A1 Wood Conversion Kit [King Arms] 3 pcs $110.19
Delivery Method UPS Express Saver Courier Delivery $39.00
Total amount $149.19
Assembly Sling Attachment points on fore grip and stock.
V Production International Company Limited
(Country of Origen) Taiwan
Address: No. 321 Hsi Nann Road See1, Wurih Dist,
Taichung City, Taiwan 41465
AS-M79P-06-A01 2 ea. $10.00
SCR-ST-3M5x16Z-A01 4 ea. (Screws) $4.00
Shipping Cost Shipping $22.00
Bank fees $1.80
Total Amount $37.80
Total Costs $186.99
So now you have full disclosure of the costs and shipping. All the parts came very quickly (my opinion) and after ordering arrived swiftly. The wood furniture came in a cardboard box with KING ARMS Logo large sticker on the box end and the wood furniture was wrapped with bubble wrap individual bags and with a darker stain than the UMAREX paint/color. The king Arms finnish on the wood I can only describe as a strong Plastic coating (not polyurethane or varnish) finish.
I intended from the start to refinish the furniture when I was done with the fitting.
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Fantastic! Thank you for all this effort and info.
Please post pics of this whenever you can. I guess you’re going to strip the wood and put a different finish on it?
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I already did last week. I have an issue (moving to a new video editor) so pictures for now. It took almost a week between stripping, stain, (wait 6-8 hours for drying between coats) and then the final Polyurethane (three coats, 6 hour between sanding/application); so yes, it took a week.
I made a stand for each piece, no touch and no drop. It was also the coldest week we had in awhile.
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Now comes the the fitting for pistol grip or what some refer to as the "rear grip'.
Again I will pictures pictures to show my work.
This one presented me with the most challenges; the main challenges are:
1) the sizing of the inside of the grip.
2) the angle and depth of the bolt hole. Both the King Arms and the UMAREX BB gun on the inside of the grip are situated very differently. Specifically UMAREX's M1A1 has a very deep bolt hole in the bottom of the grip on the outside of the grip. I can only assume the the Airsoft gun doesn't.
That means the the bolt has to be longer to reach the bolt threaded hole in the UMAREX BB gun. Secondly some removal of inside wood on the pistol grip needed to be removed as the grip did not fit. Removing the front inside wood was easy as chillising and filing did the trick. When that was finished I used some wood filler putty to make an exact fit.
The hard part came with after filling (wood plug) the original hole then planning to drill a new hole 'WITH THE CORRECT ANGLE". The pictures will show how I did it.
I was surprised to find that the bottom and sides, especially the side,s were quite thin, I used a 3/4 inch wooden rod cut to
to the specific length to cover the distance to the threaded hole in the grip. If this is not done the bolt will apply pressure on the thin bottom of the pistol grip; cracking the grip on the top, sides or bottom or all three. The counter sunk bolt hole has to match the angle of the threaded bolt hole. I measured the angle and drilled. It fit.
I was not happy with gust a small wooden doll at the bottom it needed more renforcement on the bottom. So I filled the empty space at the bottom of the outside of the wooden peg with a hard plastic resin. So the metal part of the UMAREX thread post has all pressure on the wooden dowel \, that is why it needs a longer M6-1.00 bolt.
Again I will pictures pictures to show my work.
This one presented me with the most challenges; the main challenges are:
1) the sizing of the inside of the grip.
2) the angle and depth of the bolt hole. Both the King Arms and the UMAREX BB gun on the inside of the grip are situated very differently. Specifically UMAREX's M1A1 has a very deep bolt hole in the bottom of the grip on the outside of the grip. I can only assume the the Airsoft gun doesn't.
That means the the bolt has to be longer to reach the bolt threaded hole in the UMAREX BB gun. Secondly some removal of inside wood on the pistol grip needed to be removed as the grip did not fit. Removing the front inside wood was easy as chillising and filing did the trick. When that was finished I used some wood filler putty to make an exact fit.
The hard part came with after filling (wood plug) the original hole then planning to drill a new hole 'WITH THE CORRECT ANGLE". The pictures will show how I did it.
I was surprised to find that the bottom and sides, especially the side,s were quite thin, I used a 3/4 inch wooden rod cut to
to the specific length to cover the distance to the threaded hole in the grip. If this is not done the bolt will apply pressure on the thin bottom of the pistol grip; cracking the grip on the top, sides or bottom or all three. The counter sunk bolt hole has to match the angle of the threaded bolt hole. I measured the angle and drilled. It fit.
I was not happy with gust a small wooden doll at the bottom it needed more renforcement on the bottom. So I filled the empty space at the bottom of the outside of the wooden peg with a hard plastic resin. So the metal part of the UMAREX thread post has all pressure on the wooden dowel \, that is why it needs a longer M6-1.00 bolt.
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Nice work! That’s a tough job with a hand drill. I went through a similar exercise fitting a HW75 grip onto a HW45 …. had to drill two deep precision holes and I made up a jig for the job. But I also had the luxury of a mill at my disposal
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That is nice! I used to have a lathe, drill press, then I got a job the folkes sold the house and I had no place to store the equipment. I am lucky that I am good with tools. All of those hobbies paid off. I am after all a cybersecurity guy.
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DONE! UMAREX M1A1 Thompson Wood Furniture By king Arms, fitted and Stained!
It has been a little bit of a challenge; it turns out the hard part was the staining, that is because I did not have much experience with staining. I have pictures below of the Umarex M1A1 Thompson with the UMAREX plasticware furniture below as a comparison. The hardest part was the pistol grip, the easiest were the fore grip and the stock.
I do want to remind anyone who cares that I did not alter the UMAREX gun at all. The plasticware is now in the UMAREX box with all of the original hardware (bolts, Trunnion and sling hardware). I can bring it back to factory original at any time I wish.
It has been a little bit of a challenge; it turns out the hard part was the staining, that is because I did not have much experience with staining. I have pictures below of the Umarex M1A1 Thompson with the UMAREX plasticware furniture below as a comparison. The hardest part was the pistol grip, the easiest were the fore grip and the stock.
I do want to remind anyone who cares that I did not alter the UMAREX gun at all. The plasticware is now in the UMAREX box with all of the original hardware (bolts, Trunnion and sling hardware). I can bring it back to factory original at any time I wish.
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That is just beautiful and awesome looking. I've always wanted a real Thompson (well, a semi-auto version/clone of one). I think I might copy you and do this myself to scratch that itch.
Now it only needs the drum mag to go with it.
I'm a little hesitant with it being from Umarex, as I've heard some iffy comments about them. How do you like it?
Now it only needs the drum mag to go with it.
I'm a little hesitant with it being from Umarex, as I've heard some iffy comments about them. How do you like it?
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Manlaan,
Yes, so have I wanted a real M1A1 Thompson... for $25,000 (minimum plus the Tax stamp and approval) dollars The ammunition .45 cal by the bucket. WWWWAAAAYYY to expensive. That is why I bought the UMAREX and you do not have to go to a range to shoot it if they allow automatic weapons at the range. I am totally NOT into Airsoft.
I have had my Umarex M1A1 for.. let me see... I had to look it up... 3-26-2020 is when I received my Umarex. So a little more than 4 years now. I also bought 3 extra clips.
The only problem I ever had with it was when I (my own damn fault) jammed the bolt forward because it was stuck. it was an easy fix (I forgot it was a BB gun) I even made a video about it fixing it; simple. I made a video about separating the Upper from the lower receiver, if I had known about that I never would have jammed the bolt forward to begin with.
If you decide to get one buy 100% silicone oil for the gun and the BBs. I think I have shot maybe 10k- 13K of BBs out of the gun, maybe more. Just remember it is a C02 BB gun with rubber seals DO NOT USE Gun Oil. Keep it well oiled with 100% Silicone oil and add some to the BBs in the magazine and it will not fail you.
I also purchased a MP-40 and a M3A1 Grease gun from UMAREX, all of then are doing just fine and all them have 3 extra clips and carry bags.
How do I like it... I LOVE THE GUN; well let me see...TALK ABOUT FUN.The first time you fire it in AUTO you will want extra clips! I am now waiting for Spring (above 50 F and Summer).
The Umarex Thompson M1A1in this picture still has the factory plastic furniture on it.
Yes, so have I wanted a real M1A1 Thompson... for $25,000 (minimum plus the Tax stamp and approval) dollars The ammunition .45 cal by the bucket. WWWWAAAAYYY to expensive. That is why I bought the UMAREX and you do not have to go to a range to shoot it if they allow automatic weapons at the range. I am totally NOT into Airsoft.
I have had my Umarex M1A1 for.. let me see... I had to look it up... 3-26-2020 is when I received my Umarex. So a little more than 4 years now. I also bought 3 extra clips.
The only problem I ever had with it was when I (my own damn fault) jammed the bolt forward because it was stuck. it was an easy fix (I forgot it was a BB gun) I even made a video about it fixing it; simple. I made a video about separating the Upper from the lower receiver, if I had known about that I never would have jammed the bolt forward to begin with.
If you decide to get one buy 100% silicone oil for the gun and the BBs. I think I have shot maybe 10k- 13K of BBs out of the gun, maybe more. Just remember it is a C02 BB gun with rubber seals DO NOT USE Gun Oil. Keep it well oiled with 100% Silicone oil and add some to the BBs in the magazine and it will not fail you.
I also purchased a MP-40 and a M3A1 Grease gun from UMAREX, all of then are doing just fine and all them have 3 extra clips and carry bags.
How do I like it... I LOVE THE GUN; well let me see...TALK ABOUT FUN.The first time you fire it in AUTO you will want extra clips! I am now waiting for Spring (above 50 F and Summer).
The Umarex Thompson M1A1in this picture still has the factory plastic furniture on it.
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Outstanding job, well done! Now you’ve got me wanting one. I do have the MP40 and KWC M712 and am very happy with both.
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Well no drum magazines on the UMAREX M1A1 thompson, only stick mags. Sorry. I do not know anyone who makes a BB or airsoft Thompson that can use a drum mag.That is just beautiful and awesome looking. I've always wanted a real Thompson (well, a semi-auto version/clone of one). I think I might copy you and do this myself to scratch that itch.
Now it only needs the drum mag to go with it.
I'm a little hesitant with it being from Umarex, as I've heard some iffy comments about them. How do you like it?
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I believe Cybergun (?) has an airsoft version with a drum mag. If it’s the one I’m thinking of then it needs batteries as well as co2.
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I do not know anything about the battery and Co2, I think it is just a battery; but again I have no idea.
Maybe the King Arms wood kit will fit. I suppose but I do not know; in any case if it does then you may decide that you do not have to strip, and poly coat as it as it comes with a darker color from king Arms and looks much better than the mustard color that the plasticware of the UMAREX.
I do not have any experience with airsoft guns. I have shot some but I am not interested in them. You maybe able to order it from the airsoft company that you order it from installed. Good luck.
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Same here, I have no experience or interest in airsoft stuff.
I briefly saw an add from another company that offered the Thompson with both a drum and real wood furniture (.177 cal). I thought it might have been KWC but now when I check their site there's no such thing. Wherever it was, I do recall that it was expensive and on backorder.
If the Umarex MP40 is any indication, then I would expect the Thompson to be every bit as much fun!
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Borne2fly:
Look at" King Arms". They are the ones that offer a wood stock and the Cybergun Airsoft M1A1 with the drum magazine if you buy make sure to use the battery and NOT the Green gas option. They are the ones that I bought the wood furniture from. I looked at it today $170 dollars for the Cybergun gun and another $110.00 for the woodstock furniture. The drum is an additional $50.00 but it holds about 1000 6mm BBs. So go check out King Arms website before you make a decision.
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