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Wanting to do some work to an old pump

From what I read on the internet, which I read can never be wrong or lie, says that no matter how much the barrel tapers externally, the bore is not. Any taper internally would affect pressure retention and create blow by. Make a cool suppressor that allows for interchangeable chokes ???

You are absolutely correct Rodburner. It wasn't tapered internally. If it was, not enough to make a meaningful difference.

There are some shotgun suppressors out there. I have an acquintance in New Zealand that made a heckuva suppressor by drilling a ton of holes in a 410 barrel and covering it up with an outer tube and filling the outer tube with a bunch of boot lace eyelets. It worked surprisingly well.
Looks like the cutoff is ready for a "mic drop"... :D

Yeah, I really hated that thing.
Upon looking at it much closer after getting it removed, the inside of the choke was much larger diameter, allowing the wad when it left the barrel to fully expand and be completely unsupported, and then once reaching the muzzle end of the choke, having to re-compress back down and go through it.

For the life of me, that seems to be the stupidest idea that ever was.
I told you guys this would be a slow moving process, but I was able to get a ramped front sight for it today. I decided to use the front sight from a CVA black powder rifle. It has an old school lyman style ramped sight with a brass bead in it.

The front bead may be just a bit too tall. At least when using the low brass shells, which pattern lower. But the high brass shells (the ones I generally use in it) seem better. So, I'm not going to make any changes to the front sight at this time. I'll wait until after the barrel is reamed and threaded for chokes and then check it again after all the machinework is done. But if I need to split the difference so I can shoot essentially anything, I will after I get done with everything else.

But for now, the front sight is installed and it's straight. So, that's the main thing for today. The ramped base is the perfect height for the barrel taper and the top of the base is level with the top of the receiver. So, worst case scenario, I would be able to mill off this front bead, and would be able to install a shorter fiber optic shotgun bead to raise the POI up a little if I need to. But, that will come after it gets choked. For now, I'm content that it's straight and level.

Another big reason why I wanted this front sight base is that the attachment screws are well behind where the choke and reaming is going to be. The entire front sight sits farther forward over the choke and looks more like it's supposed to without anything interfering with each other. Also, the decorative grooves on the top of the ramp match the grooves in the top of the receiver and the two look like they always went together.

Here's a couple of pics if anyone is wanting to keep up with it.


The rear bolt is going to be replaced with a smaller head slotted 6-48 screw. But this is what I had on hand today. So, yes the head of the rear bolt is a little taller than it needs to be.


And the two test targets. The first one is a Remington express long range high brass. Box says 1290 fps pushing a 1-1/8oz load of #6. It printed higher than the federal, which I think was 1 oz at 1165 fps. So, that's what I contribute to the federal shooting so much lower comparing the two is just less velocity.

Remington express long range high brass

Federal game club low brass was just lower. Windage on both look good, so I'm counting today as a win.
Alright folks. For anyone still interested and following along, I did some more work to the front sight today. I had intended getting a fiber optic front sight, but instead of paying $16-$20 for one, I decided to just make my own and save a few bucks. Besides, it's been rainy for days and I'm bored and have nothing else to do at the moment.

I milled off the front blade that I mentioned was a little too tall before, found the center of the base, then drilled and tapped a 6-48 hole. After that was done, I screwed the 6-48 bolt all the way in so I could time the front and the back in regards to where I needed the fiber optic to be.

Marked the bolt with a sharpie, filed the round shape down flat where the marks were so the drill bit wouldn't walk off, and drilled it out. Afterwards, simply put the fiber in place, struck a cigarette lighter to melt the ends and put the screw back into the front sight base.

While not as fancy as a store bought one, it's working well and costed about 60 cents.

The fiber dot sits about half as high as the old blade that was on it over the sight line of the receiver. The height over the base with the blade was .315" and the height of the torx screw that I used was .180".

Sorry that I don't have any more targets showing patterns this time, but I don't really see the point of shooting it at the moment until I thread the barrel for the choke tubes. I already know the pattern should be a bit higher than it was the last few shots I made with it, so not really seeing the need to shoot it when I know what it's going to do.

But, this works for me, freed up the money that I was going to spend and will now let me buy the 20 ga cylinder remchoke this weekend.

I was able to order the cylinder 20 gauge remchoke tube this week but it still hasn't gotten here yet. Matter of fact, it hasn't even shipped yet. amazon is slipping !!! They usually ship within at least a day, but this is day 3 and still no notification or tracking.

Anyway, the choke is going to be one of the more tedious aspects of the build. Obviously, I don't want the choke tube to protrude too far into this barrel and cause an obstruction. So, I'm going to have to chamfer the mouth to remove enough metal so as to transition from the looser to tighter constriction.

I've thought about this a lot and have decided that I am NOT going to use any type of cutter in my lathe to do this. Mainly because the tube is thin and I don't want the cutter to snag on the tube and crumple it up like an old beer can. I've actually done that before while working on thin tubing before.

So, I got a scrap piece of wooden dowel and tapered the edge of it to the size I need and will just be sanding the edge of it manually while it's chucked in the lathe. This will impart far less pressure on it, and will also ensure that I get the taper that I want/need and I shouldn't lose any fingers by sticking it up into the barrel with the sandpaper.

Here is the "tool" I made. Yes, you can see the metal tarnish on the side of it. I tested it to make sure it worked in the old scrap piece of the barrel that I cut off.

Here's essentially the way it looked with the small piece of sandpaper on the edge.

Here's what it looks like while working on the piece

And proof that it's working. I only had the motor on about 40 rpm so it didn't rip the sandpaper out of my hand and so I could hold onto it. But you can see even after less than 2 minutes that the mouth of the barrel is starting to open up. It will take some time to get the choke tube the way I want it, but you can see the leading edge starting to take a taper. The choke will have a longer, steep taper by the time I am done with it, but you can see that this will work for the desired outcome to bring the choke tube to the correct inside diameters. *Using the scrap piece of the barrel that I cut off below was just to see if this would work and I won't need to do this to the shotgun barrel itself. I only used it to test to see whether this method work work or not.
I took the liberty of taking some pics of some of my older 12 gauge chokes for a reference. You can pretty clearly see the taper in them after they get fouled up some. I'm essentially going to do the same thing with this 20ga choke and what I was trying to show above.

Here's a cylinder bore that came with one of my guns. You can see how little taper there is to it. (*you're looking for the little ring inside the mouth of it).

And a full choke that has been used. It has a much longer taper transition and will be more like what I'm going to do for this choke.
Thanks buddy, but it's more like the mad scientist.

There is probably a valid reason why no one else has done this before. I just don't like taking no for an answer. So, I'm trying to think it through and be able to do it without causing an unsafe issue. I think I can pull this off though. I've done the research in the 3 different chokes and why I chose to use the remchoke style thread because it's the largest diameter which will cut deeper into my barrel. That should give it more than enough surface area to keep the threads engaged with each other so it don't puke out. The other two choke styles, while one of the others would maybe work, it's a couple hundredths smaller diameter than the one I chose to do. The rem style, will just get deeper into the side of the barrel making it the strongest option of the 3.

In honesty, there are two companies that will thread and make 16 ga screw in chokes. But as you can imagine, aren't cheap. Starting at $175 for just the barrel work alone and going up to $325 if you actually want chokes included. Neither option interests me at those prices. Especially since that's probably more than the whole gun is worth. Or at least more than I paid for it. I just want something that I can better use.

The gun itself is not a bad design, just that they're "older" and made by a company that doesn't exist anymore, means, most folks don't give them a second look. Despite that much of the internals is probably where the mossberg got their inspiration in the 500 models are very similar. The bolt and barrels are pretty much exact copy of the older winchester trench guns. Both have proven to work well. Smith and Wesson even bought the design and made them a few years when the owner of the company passed away. So, it's not like the gun is going to spontaneously combust.

Truth is, compared to a lot of newer guns being made these days, it has several things that I think are more desirable. Steel everything. Steel receiver. Trigger guard and assembly. Even the follower is stainless steel. No MIM parts. They don't make stuff like they used to.

Lots of companies used variable/adjustable chokes back in the day, but the one on this gun, mostly just sucked. It shot the same pattern pretty much regardless of how you had it set. And it fouled badly no matter what you did. So, this should remedy that. I want to be able to grab the full choke for when shooting at squirrels in those tall trees, or at turkey when they're 35 yards away. Or, grab a modified choke for shooting at birds and even fast moving rabbits. If I can manage to do that, I'll be content with the work I put into it.

It will still likely be several weeks before I get to rent the reamer/tap set. I was speaking with 4d rentals today and they said there were 2 people in front of me. Since they will be out of stock for at least the next couple of weeks, there was no reason for me to order yet since I can use the money for other things in the meantime. I'll just wait until the first of the year as I had originally planned to do in the first place.

However, they did tell me they were going to be replacing the tools and have already been ordered, but he didn't have a delivery date expected for them.

I have decided that instead of using the wood/sandpaper technique to open up the mouth of the choke, I'm just going to order a taper reamer. I found one for about $16 shipped. This will certainly be much neater in the end. And would ease the transition into the choke tube as well.


I also decided that I'm going to use the scrap piece of barrel to ensure the mouth of the choke is tapered right too. I cut the scrap piece of barrel to the length of the choke. Or, just a shade longer actually. This way, I can thread the scrap piece of barrel while I have the tools here and can ream the mouth of the choke to precisely where it needs to be. I'll essentially just be making the old barrel cut off a jig.

While not exactly related to the work I'll be doing, my wife asked me what I wanted for Christmas. After several times asking and me telling her nothing, I finally told her that I would like a pack of the new 16 ga wads that I've been looking at. Unlike most traditional 16 ga wads, these are unslit and have a shot cup that will hold up to 1-3/8 oz of shot, which is a lot for 16 gauge. I typically tend to only load up to 1-1/8 oz, so I'll need to get some 28 ga felt wads to put in the bottom of the shot cup to take up the extra space to give me a good crimp. I am going to try to make some loose copies of the flite control wad to get me some long range 16 ga shells. Either for turkey or squirrels that often get in the top of these old growth trees and sit there and mock people on the ground because most shells are lucky to get 45 yards up in the tops of some of those trees. So, I'm going to try to see what I can squeeze out of everything. Maybe give some of those squirrels some surprises next fall.
I hate to update the topic without having something meaningful to update, but I don't really want to bump a topic that hasn't been active for a long time either. So I'll give the details of where I'm at.

I was able to make the order for renting for the reamer and tap yesterday. But, at least to their credit, they let me know that it'll be at least 3-4 weeks before they can send it to me due to a few people in line in front of me.

Since they bill the card when you make the order, they did give me the option to get a refund since it was going to be an extended amount of time which I thought was decent of them, so they asked what I'd like to do.

Since I understand how stuff like that is, I told them I'd go ahead and just be patient and wait my turn in line since the line would probably not ever be very much shorter. So, while it would've been great to get the reamer sooner rather than later because it's already been far longer than I would've liked to finish this project anyway, it is what it is.

I did get the taper reamer that I ordered but am not going to chamfer the mouth of the choke until the last step. I may still have to reduce some of the OD of the choke tube first, and I don't want to make it any thinner than it already is until the final step of the process. It's going to be very thin at the mouth.

As for the wads that I got for Christmas, they were under the tree and I REALLY like them. Now I have something that I can use to load the Federal hulls that I have. While I don't ever plan loading the 16 ga shells with 1-3/8 oz of pellets, I checked and they at least will hold that much without overflowing out of the top of the wad. For all intents and purposes though, 1-1/8 or even 1-1/4 will be about the limit of what I would normally load with. I have a couple different brand of wads that will let me load the 3/4 and 1 and 1-1/8 oz in the remington hulls too. So, it's nice to have choices.

I cannot ever recall hearing of a factory 1-3/8 oz payload 16 gauge shell. But, for anyone trying to create a wall of pellets for turkey hunting and the likes, it's pretty neat that I would have the option to do that now.

It's nice to see some new choices so the old 16 ga isn't always being left behind.

I've been noticing, and there's several new manufactured 16 ga guns on the market this year. Stevens has a nice O/U import. Browning is making their sweet 16's. Tristar is importing a nice looking semiauto variant for under $600. It comes with 3 screw in chokes as well. It's called the G2 Viper. Blued and walnut furniture to boot. Really sharp looking guns to be honest.


Still no update on when I'll be able to get the reamer rental but with the snow falling outside, and the USPS finally decided to deliver a piece of 3/4" brass rod after holding it hostage for more than a week, I was able to make some progress today. Though, not be able to do any work to the gun itself.

The main reason why I needed the brass rod, was one thing that is necessary to do this is a barrel shim. It slides into the barrel precisely the correct dimensions and has a hole through it to keep the tool straight with the bore as you're cutting the threads and doing the work. Without a proper sized shim, there would be very small likelihood of success threading it. I had intended to use a piece of aluminum rod, however, the rental company warned against it because of the possibility/likelihood of the aluminum getting hot and galling either the barrel or the tool.

Here is a quick snapshot of what the brass shim looks like in use. I took this pic while using a 12 ga reamer and tap in an earlier project, but does show the brass shim.


Since there are no 16 gauge shim sets available (to rent or purchase or otherwise) I had to resort to making my own. And thus, the need to purchase a small piece of 3/4" brass rod, that I turned down on the lathe until I could barely slide it into the barrel. The last several passes on the lathe were the most stressful part of that process because removing too much material, would've rendered it useless. But, I was able to get the diameter that I was needing after some time on the lathe.

I have not drilled out through the center of the rod to accommodate the tool itself yet. Since I've never had a 20 ga tool, I'm going to refrain from drilling out a pilot hole until I find out what the diameter of the shaft on the tool is when I get it in hand. Again, that is not a step that can be halfway done right either. It needs to be a precision diameter so the tool doesn't have too much slop in it, again, causing the reaming and threading to be off.

So, here's a quick snapshot of what will be my 16 gauge shim after I turned the diameter down to the proper size. Maybe someone will appreciate the machinework.


I have used a center finding bit to start the bore hole, but it's barely into the metal. It's not really bored into more than just to get below the face. Only enough to help direct and hold the bit in the center of the work piece when I do that step in the process so the bit doesn't try to walk or flex as it's starting, which would likely cause an offset hole through the rod, which again, would mess up the thread tolerances resulting in bad ju-ju.


Below you can see how it fits in the barrel that I'll be threading. Just enough tolerance to where it slides and fits into the barrel. Precisely how it should be. No wiggle room at all, but not a press fit either. I'm well satisfied how this part turned out.

Remove the pineapple part and make a homemade suppressor and screw it on. The birds won’t know what hit them!
I actually know a few guys who have suppressed their shotguns. I thought about it. Never did it though.

I can PM you some pictures of one of them if you'd like. He asked that I not share them publicly, but if you'd like to see how it turned out, just let me know.
Well, after the allotted month I was expecting, unfortunately, I'm cancelling my rental order. I contacted them and was told today that there was no change in order status and no ETA.

So, I asked them to cancel and refund the order.

This sucks too because I've already bought the 20 ga choke, the brass rod that I machined down to make the barrel bushing for. There goes $50 wasted and down the drain.