Rear sight riveting?

[p51]

I have an Indianapolis Ordnance M1A1 BFONG kit that I handed over to a local gunsmith but he's stumped on how to rivet the rear sights in place.

Any ideas? He says he'd essentially need an actual set of tools for a Thompson to complete this. It's stopped the project for now.

Edited June 6, 2024 by p51

[TennesseeTaylor95]

I'm still a novice so I could be off in left field here but I thought that riveting a rear sight on a TSMG was a relatively easy thing to do considering you have the correct rivets and a bucking bar/anvil (assuming that you're just going to set the rivets by hand with a punch, which isn't technically correct for a production gun but does get the job done in the grand scheme of things). Having no first hand experience with the Indianapolis Ordnance M1A1 BFONG, I don't know if they have the same countersunk rivet holes for the rivet heads to stay in without protruding into the bolt pocket or not. Assuming the rear sight rivet holes are countersunk and you have the correct countersunk rivets, then it should be as simple as inserting the rivets from the inside of the receiver, place a bucking bar/anvil in the bolt pocket to support the rivets, install the rear sight on the 4 rivets sticking through the top of the receiver, and then proceed to rivet the rear sight one rivet at a time.

Do you have any pictures of the bolt pocket where the rear sight rivet holes are? 

 

 

Edited June 6, 2024 by TennesseeTaylor95
Info added

[p51]

The gunsmith has the gun right now and he's officially given up on any way to rivet the rear sights in place. The only gunsmith he's found anywhere who will take it on in the US is a guy in New York state and other than California, that's the last place I wanna send this.

My guy here says he can't drill and tap those holes because there's nit enough metal to guarantee that they won't wear through with the rattling of use.

Had I known it would be this tough, I doubt I'd have bought this stupid thing.

[68coupe]

OK. There are several members of this forum that should be able to help, if they're not too backlogged. I hope my shameful plug is permitted and if not, please delete it. If the members of this forum can't help, though I don't have personal experience with them, YET, you could try PISCO (Pacific International Services Company) in Oregon. It was founded and formerly owned by the late Bob Dunlap, of the AGI video series of gunsmithing videos. I currently have my C96 Mauser with them for barrel relining. They have an excellent reputation, and so far, have been easy to work with, and answered the phone immediately.

PISCO
140 East Third Street
Coquille, OR 97423

Phone (541) 396-5558
Fax (541) 396-2347

pisco@piscogunsmithing.com

V/R Karl, 68coupe

[TD.]

Since your in the Pacific Northwest, how about Board member PK. in Delta, Colorado. I am sure he could do the job perfectly.

You can contact PK. at: p-k@q.com

Give PK a couple of days to reply. He is always very busy.

[Chappy]

Unfortunately I had my rear site riveted on a shooter WH. Then I found I could not put on the BRP red dot base.  On a WH, I think a red dot is a good idea for just a shooter. But they are now pinned and riveted. I am 100% happy with Dan's job at bringing my "pain in the butt" WH into a solid shooter.

Chappy

Edited June 12, 2024 by Chappy
clarity

[anjong-ni]

Perhaps the "thinness" of the material has something to do with the blank-firing conversion.

It would be very entertaining to see a photo of what's INSIDE that upper receiver.

We've seen ReCon Bob's blank gun here on the Forum. It's an engineering marvel!    ...Phil

[deerslayer]

Ive riveted a rear sight  to an Indianapolis ordnance receiver before.  

Dan

[68coupe]

Dan, I was hoping that you'd chime in.

Karl, 68coupe

[PK.]

How thick is the top of your receiver? 

[p51]

I still don't have it back from the gunsmith yet to answer any questions. I'm quite bummed about that as I'd given him a deadline of two weeks before a big show where I wanted to display it and here we are well after that and I'll be lucky to get it back this week, still incomplete. I never would have assumed this would be such a problem!

[68coupe]

1 hour ago, p51 said:

I still don't have it back from the gunsmith yet to answer any questions. I'm quite bummed about that as I'd given him a deadline of two weeks before a big show where I wanted to display it and here we are well after that and I'll be lucky to get it back this week, still incomplete. I never would have assumed this would be such a problem!

I'm so sorry to hear that. At least that gunsmith was cautious and didn't wreck your gun. You're in the Pacific NW. How close are you to Coquille, OR? If it's close enough, you may be able to physically take it there. It should be a 2hr job, given the right parts, equipment and tools. I recommend a phone call to set it up, prior to hauling it there out of the blue. I've done the sight on my own firearm, but am not yet licensed, AND I'm in FL. I know I'm not a big help myself. I'm only offering a possible solution to your dilemma. I sure hope it works out for you.

Karl, 68coupe

[reconbob]

       I just riveted a rear sight and figured I's post pictures of the setup. It's low tech.

but there is really no other way.

The receiver is clamped down on top of a special anvil so all 4 rivets are held solid and there is

no looseness or vibration when the rivets are stuck. Clamped to the table of one of the milling 

machines as even a sturdy workbench would not be solid enough.

This is the anvil with hardened dowel pins properly spaced to engage the heads of all 4 rivets. The

set screw at the back is adjusted so when it is against the rear wall of the bolt pocket the anvil is

in position. The width of the anvil is the same as a bolt - a tight sliding fit in the receiver.

   I use a heavy duty starting punch with the tip ground convex to flare the heads when struck. I use

a 2 lb. hammer and do 4 strikes in a 4 leaf clover pattern.

Bob

 

 

[2ndArmored]

while "The Anvil Chorus" plays in the background...

[p51]

On 6/18/2024 at 5:30 PM, 68coupe said:

How close are you to Coquille, OR? 

 I'm pretty far from you, almost a 6 hour drive.

My problem is everyone into WW2 stuff I know locally says, "Oh, I know a guy" but when I press them for a phone number they either ghost me on it or later say they haven't heard from said expert in a very long time (and also not giving me a phone number).

This thing is a BFONG (ATF approved non gun blank shooter) full auto mounted on an original lower and I do NOT wanna mail the thing anywhere.

Worse still, the safety has something wrong and the third time I pulled the bolt back it completely locked into place. I have no gunsmith tools to try to get the upper off because I can't get the trigger to engage and release the bolt.

For all the money I have in this, I haven't been able to even test fire it and I can't even display it at events without the rear sight in place. It's been a collasal disappointment that I have no idea IF it'll be fixed, let alone being able to figure out a timeframe...

[TD.]

If mine and I lived in Oregon, I would contact PK. in Colorado and discuss. You can send it to him USPS Registered Mail. That is how it will be returned. 

[deerslayer]

Everything was probably mailed to you in the first place.   Registered insured usps mail to a gunsmith and get it fixed.  No reason to worry.

[spall]

Here's the thing- you've found the greatest collection of Thompson knowledge and gunsmithing skill on the planet. You're getting advice from the people who have literally written the books on Thompsons.

Transferable Thompsons get mailed almost every time they are sold (value $20k-50k +)

If you want it done right, you've found the right place. Research some of the folks who've offered to help you, call them, and then mail it with insurance.