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Discussion Starter #1
So was working a few projects with extra time I’ve had since Covid. Had my 1919 out tinkering....and my trunnion is starting to go, I assume due to link use wear.
Anyone ever replaced one before? Have pics or advice?
I built the gun myself, with parts, a rivet kit, and a BFH, but it’s been a while. I don’t want to create any other issues trying to fix the trunnion.
Any opinions or insight are appreciated. Thanks!
 

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How bad is it? Have you tried running it with a trunnion protector to extend the life of it? They are not to bad to do but I would recommend dry fitting it first then filing most of the feed way areas before riveting it in place because once you rivet it in place you will only get a very short file stroke which takes longer. It is always faster and easier to do the bulk of this work with the trunnion out then I fine tune it after riveting.
 

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Discussion Starter #3
I’ll drop some pics shortly.
That said, I’ve always run a trunnion protector, for two reasons:
1) Russ, your advice, and
2) the trunnion wasn’t awesome to start. Such that before I parked the receiver, I had a bead of weld added. Even that hasn’t seemed to do the trick.
I built the gun mainly for reenacting, as an accessory for my ‘44 Willys MB, and to see if I could. My point there is I don’t fire it a ton, but I want to be sure it is as safe as a firearm I cobbled together with parts that are mostly 70 plus years old can be!
 

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Discussion Starter #4 (Edited)
Trunnion feedway

So, I’m trying to decide if I can get another 300-500 rounds out of this? I’m planning a trip to my folks place in Texas later this year, and Dad has a far more heavy duty drill press than my vintage bench top unit. So I’m trying to decide whether it makes sense to go ahead and drill the thing out then, or if it can wait a while.....
 

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Should be just fine for that amount so have fun with it until then. Do you have a replacement already?
 

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KMP's new made ones work nice. Have used more than one and havent had any problems with them. Call them up tomorrow and see if they have them in stock.

If you have wedge bucking bars the job is easy. Drill and punch the old trunion rivets. Spread the plates slightly and slide out the trunion. You'll spend more time degreasing and refinishing the receiver casing than doing the work.
 
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We ran some 1919s that had the trunnion worn through and they still worked pretty well. Didn't look very good but post samples don't care. I made up a copper bar to fit in the trunnion and welded them up and milled them flat again. No more holes and 15000 rds later they were still pretty. I have no idea how many rounds it takes to wear out a trunnion. I have a feeling that sitting in a sand pile while you do it has something to do with the wear. Just the links aren't as much of a problem as guys think.
Just my thoughts.

Frank
 

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Discussion Starter #9
KMP has them in stock for $350, so I’ll be ordering one from them soon, to have ready....
Thanks for all the advice, gentlemen!
 

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Discussion Starter #10
One last question....anyone know what the minimum would be for a hydraulic press to crush the rivets with less John Henry drama then my four pound hammer? If I could pick one up reasonable, it might encourage additional projects too...(insert Vincent Price laugh here) 👹
 

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The average Browning rivets only requires about 4 tons of pressure so a HF 12 ton press is more than sufficient for the average builder.
 

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If you get a press do some practicing first until you get the feel for it. I only do the initial set of the trunnion rivets with the press and then use a 1" diameter x 6"L piece of tool steel with a polished face as a punch if you will so I can work it in and manipulate it to ensure it gets a good fill. A little trick I picked up from Lucky13 years ago and it also saves you from slipping and marring the box. I also have aircraft grade rivets guns that I will use depending on the project but either way if you have any questions you have my number.
 
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