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Posted: 5/13/2025 2:49:48 AM EDT
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This one is the third in a gripped series I've been doing. It's also the shortest at a tick over 8 inches. Just completed shortening of the mag tube last week. She will hold three, 3 inch magnums. I don't intend to shoot three incher's, but thats how much room is available, and one in the pipe. Most of the other work was completed a short while ago including the turning of the barrel and cutting and finishing the length. Working the rib over and cutting it to its length. It will have a job to do in the future. Barrel diameter finished size will be .875. Its at .890 right now. The turned part of the barrel is 2" long now but soon to be 2.250 long. The barrel ring is not made yet as well as a special barrel mounting ring for another assessory. The barrel ring will be a thermal fit to fix it on the barrel. Front face of the barrel ring will be 1/4 to 1/2 from the muzzle. Going to set it up for a suppressor. Barrel will be threaded .875-32. Already worked over the magazine nut and shortened the magazine spring. There will be a barrel shroud mounted to that "other" assessory ring. I have a TAC 13 that got me started down this path. Great shotgun. I now have an 11" with a buttstock, a 10" with a Raptor grip, and getting closer with this 8". It will use a cut down epoxy filled factory stock for the grip. (Top gun in the 1st picture) A few pieces yet to make: The barrel ring to secure the barrel. A front mount for the cut down handguard so its secure but still dissasemble with the mag nut.. The assessory ring. The upper barrel shroud. There will be no sights. I re-configured it for testing. I put on an original stock to have a solid shoulder to fire from. Don't think it would be a good idea to fire from the hip to begin with the testing. After I get it running off the shoulder, on goes the cut stock and test again but it should be good. The blue tape in the pictures is being used as dimensional spacers. It will not have a barrel clamp when complete. This gun was pretty much new. It has maybe 100 rounds I put thru it to make sure it ran as it should.   , ,  |
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Back on the 8" V3 today. I drew up some prints for a couple of pieces (prototypes) and had them printed at my machine shop. Arizona Quality Machining in Phoenix. They have added printing to their array of machining capabilities. Sent them the prints yesterday and the parts were complete by noon today. Thats fast and right to dimension. The parts came out perfect. They hit the dimensions I gave and once the barrel was ready, we installed the parts. I had originally turned the barrel to .890 diameter and 2 inches long. Today we turned the barrel to .875 and 2.5 inched long. The .875 is to accomadate adding 7/8-32 threads at a later time for a muzzle brake or suppressor. The ring with the lug and 2 holes is for a combination heat shield and upper hand guard. Its just the front mount. There will be 4 more holes added to the rib to finish it. These parts are prototypes and made of polymer. They will be made of stainless next week. This is proof of concept today. Both stainless rings will be thermal fit to the barrel in the location shown in the pics. The front ring will secure the barrel to the receiver. There is a nice shoulder for the rings to butt up against at the 2.5 inch dimension. Wow! was I happy when the parts went together as designed. Near perfect or maybe perfect snug fit. Next up is to work the handguard to fit, secure the handguard to the gun, and make the heat shield/upper handguard. This has been a lot of fun to get it to this point. Mostly to plan with a few minor changes along the way. Here are some updated pics for the work performed today.    ,    
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We have an update. Still moving forward bits and pieces at a time. I used this V3 as a guinie pig. It is built to be fired from the hip or low position. I decided it needed to be set up for choke tubes and an upper hand guard for the off hand to wrap over the top of the barrel. I had Pacific Tool and Guage build me a Rem choke reamer and tap. This was the first use of these tools, also just my second choke install. The first choke I did was done without these tools. Bored the barrel for the choke tube and used a tap for the threads. The choke installed was the Beretta Mobil choke. Threads at the muzzle instead of at the bottom of the choke tube. That job was pretty easy to do. Just a bored a couple of diameters and ran the correct tap at the muzzle. My set-up wasn't ideal as I was using just a lathe and a 3 jaw chuck. Piloted reamer in the tail stock. It came out very good. The fit was to the tool size so that was good. I didn't induce any issues during the process. So a few pics of ththe finished muzzle with no choke, choke installed, and extended choke adapter for Saiga 12 muzzle devices. The upper handguard was pretty simple, just had to get the dimensions correct and to fit the barrel as good as I could for the first one. This was printed using carbon reinforced polymer. Pretty tough stuff. Might be a small change to it and print another one. It was designed to mount to the vent rib with six 5-40 button head screws. Some taper, some angles involved to get the fit right. Matt at Arizona Quality Machining is a whiz at drawing this up and making changes for the printer. Big thanks to Matt. I added vent reliefs over the factory vents in the hand guard. I gave the machine shop new prints for the barrel clamp and upper hand guard mount to be made from stainless. These two items with be thermal fit to the barrel, That will keep them in place during the 12 gauge recoil. I also designed the lower handguard mount (front stop mount) to keep the factory hand guard firmly in place, held by the mag nut. That prototype is being printed as I'm doing this update. It will be checked for fit and function tomorrow. If all is good, the part will be made of either aluminum or delrin. We'll see what we have once printed. Either way, it will be a CNC part. Here's some pics.  ,  , \     |
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Quoted: Not sure how I missed this. Very cool. I might have to have to try it with a vertical pistol grip at least once if it were mine. ERGO makes a pretty nice adapter (Aluminum) and adds the AR15 buffer tube and a mount for any AR15 pistol grips. You'd have to plug the buffer hole if you just want to use the grip. I can make just a grip adapter if I give it some thought or modify the ERGO unit.(remove the buffer tube mount) |
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Quoted: Doesn't the Tac 13 adapter allow use of 870 grips and stocks. Yes, to some degree. If you have a pistol grip for the 870, its not going to fit well. The adapter moves the grip too far away from the trigger housing. Also the back of the V3 receiver has an angle of 7.5°. The 870 is 15°. Adapter fixes that. I have a Hogue Tamer pistol grip for the 870. Tried it and its a no go. It will mount up alright but the fit is too far away from the V3 trigger, which is further forward than the 870 trigger. Talk about LOP..... It's not likely there is a fix for this issue unless someone makes a different pistol grip mount for the V3. I have a couple of ideas. |
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I have done some work to the handguard, closed in the front, created a mount for the barrel nut to secure the handguard Had some parts printed, glued them in and re-cut them to finish. Looks like it's going to work perfectly. I also printed a new top hand shroud to cover the barrel's vent rib. Pics to come shortly. |
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Quoted: ...The first choke I did was done without these tools. Bored the barrel for the choke tube and used a tap for the threads. The choke installed was the Beretta Mobil choke. Threads at the muzzle instead of at the bottom of the choke tube. That job was pretty easy to do. Just a bored a couple of diameters and ran the correct tap at the muzzle. My set-up wasn't ideal as I was using just a lathe and a 3 jaw chuck. Piloted reamer in the tail stock. It came out very good. The fit was to the tool size so that was good. I didn't induce any issues during the process. @Namsag What thread size tap did you use for the Mobil threading? Was it a readily available bolt hole style tap - or a piloted choke tube tap (as you have for the Rem-Choke)? |
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Wow! I did a quick look for the tap I used and didn't find it. I will look some more tomorrow. Figures out to be .810 x .03937 or 20.6mm x 1mm. I need to find the tap I used to be sure. I've slept a few times since doing that choke in the VR80 external choke project. I might have used a 20 x 1mm plug and then a bottom tap. Leaning in that direction. I bored the holes on the lathe to the correct sizes. It was a pretty simple job. Doing a barrel without a piloted reamer and tap could present problems. Concentricity to barrel ID. I will take a run at this again tomorrow. If I don't get back to you tomorrow or day after, come at me again as a reminder. Lot going on right now. Rex |
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Quoted: @Namsag What thread size tap did you use for the Mobil threading? Was it a readily available bolt hole style tap - or a piloted choke tube tap (as you have for the Rem-Choke)? Here is my answer. Somewhat involved. My mobil choke threading tool measures .822 across the threads. These are square threads. 21 millimeters is .827. That being said. The mobil choke is a 21 millimeter square thread. This is done to produce stronger threads, less suceptable to damage from handeling. square walls of the thread. So square threads being used in standard threaded hole. No square thread tap available. The choke reamer tool has a finished diameter of .788 for the total length of the choke hole. The threads are cut in this diameter. So it is the (tapped hole diameter) I measured a choke tube. .785 diameter on the barrel and .810 across the threads. So you need a .788-.789 hole for the threads. 2.010 inches deep, flat bottom. Use a M21 x 1 tap. Tap the hole far enough for complete thread engagement of the choke and that the choke seats on the bottom of the hole. I used a plug tap to get the needed threads and finished with a bottom tap to end the threads. Doing a couple of extra turns on the tap is OK as the choke seats on the bottom of the hole. This will give you a pretty nice fitting choke tube sitting flush with the end of the barrel. If you plan on using extended choke tubes, they are a few thousandth of an inch longer. Thats so the choke still seats in the bottom of the hole and not on the end of the barrel. I have a lot of rounds thru this choke set-up with no discernable wear. The tools, piloted choke reamer and tap.  This is a good look at the square threads of a Mobile choke. I think all chokes have square threads but not 100% sure.  |
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Update as of 01/08/25 Finally got the gun out for some function testing at an indoor range. It was one of four so about 15 minutes of testing. One hour was scheduled for range time. The ammo used was all slugs so I was limited as to the loads I had and could test. The results obtained were with one ounce slugs. Not a lot of choices as to velocity and load. 1 ounce slugs at 1200 FPS and 1350 FPS. An improved cylinder choke was used. It cycled the 1200 FPS Remington Slugger Managed Recoil but not with authority. It did eject the spent hulls. A really dirty gun might not. The 1350 slugs cycled with authority. Having an 8" barrel cost valuable dwell time needed for strong cycling. The 1200 FPS (1 ounce) ammo is not my choice for this short barrel semi auto. I cannot modify the gas ports and the gas block on this gun is vented. Closing off the vented gas block might make this gun run great. We'll see. A heavier load, 1 1/8 oz at 1200 FPS would cycle stronger and improve reliablity. This gun also has a low round count. More rounds thru it might improve the cycling of the low powered slugs. A shoulder stock was used instead of a raptor or pistol grip. The shoulder gives best condition for this test. It will have a modified short grip or a Raptor on it in it's final configuration. As it was tested  The front with the closed in forend and with the upper handguard. Magazine cap recessed about 1/8 inch. A lot of sanding and prep needed on the upper handguard as well as mounting it securely.   The bones of the business end.     The upper handguard support ring and the barrel ring are 304 stainless. Tough stuff. They are thermal fit on to the barrel. The first ring went on exactly as planned. Slipped on and located without issue. Not true with the barrel ring. Cooled of too much and became an interferance fit. Got it part of the way on and it started tightening to the barrel. Had to press it on the rest of the way. Produced some light galling on the barrel. It will get a stainless sleeve to cover the marks. 3 screws will secure the upper handguard. Then on with the Cerakote to finish this up. |
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It's done. Today, I picked up the last parts from X-Werks who did the Cerakote. Another project off the to do list. It has been a fun one for sure. Went outside the box to make it pretty short. Removing the barrel ring and creating another method to secure the barrel because it's so short. Even changed to the Raptor grip. This one is an original Remington sourced part. It ended up at 21 3/4 OA. It feels compact and solid when handling. I may add a strap under the forend like the TAC 13 comes with. It's tight for room on this one. We'll see. The strap works really well on the 13. The upper rib handguard is for thumb over or over hand grip. Probably not a project for the average gun enthusiast but have at it if it floats your boat. It's now a 3+1 gun. Lost a round due to it's length, shortening the mag tube. Shouldn't even need 4 rounds for home defense!!!!! Destined for #0 or #1 buck, 1 1/8 oz load. Picture with it's brothers in arms. The other short V3's I have. And an original TAC 13, it's the longest.       All together now. 8", 10", 13", and 11" folder. Where's the 12"? The 8" and the 10" use my printed adapter. The red dot on the folder is a Votatu. Been flawless since installation.  
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Quoted: Mossberg now has a semi- Shockwave, and some folks call the 12 ga mini-shells "Hater Tots". The Aftershock? Not sure if this is the model semi auto you we're referring to but it's the newest out by Mossberg. The new 990 is a decent piece. They offer the SBS version as well. Don't know if it's out yet. That functions pretty well and makes it more economical to build. I'm not a real fan of the recoil (action) spring going around the magazine tube unless its a 3 round tube. Means everything is closer to the receiver. My issue is (you probably already figured it out) it keeps you from making it any shorter. The action spring, along with some other parts, occupy that area where you need some space. On the 10" Remingron 1100 I did, I shortened the action slide, lightened it, moved the barrel ring and gas ports but no spring to mess with. You would also need to move the gas ports closer to the chamber. Lots of work and other modifications needed. The barrel ring looks to be around the 12" mark. Gas ports are there. OPSol Mini-Clip kit for Mossbergs line of their pump models for the Hater Tots. Not semi compatible. All of this is what makes the V3 platform so awesome. Recoil springs IN the receiver, only the gas pistons external. I love it. I did look at the 940 and it could be made to run shorter if I could get to the gas ports. Go here to see a breakdown. https://thebiggamehuntingblog.com/mossberg-940-pro-field-review/ Taper of the barrel prevents moving the barrel ring because the piston would hit the barrel. Not a candidate for shortening the gas system but maybe an inch. Piston only travels 5/8 of an inch. You might get the barrel to the length of the mag tube. That would be it with the 940. |
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Quoted: The Aftershock? Not sure if this is the model semi auto you we're referring to but it's the newest out by Mossberg. The new 990 is a decent piece. They offer the SBS version as well. Don't know if it's out yet. That functions pretty well and makes it more economical to build. I'm not a real fan of the recoil (action) spring going around the magazine tube unless its a 3 round tube. Means everything is closer to the receiver. My issue is (you probably already figured it out) it keeps you from making it any shorter. The action spring, along with some other parts, occupy that area where you need some space. On the 10" Remingron 1100 I did, I shortened the action slide, lightened it, moved the barrel ring and gas ports but no spring to mess with. You would also need to move the gas ports closer to the chamber. Lots of work and other modifications needed. The barrel ring looks to be around the 12" mark. Gas ports are there. OPSol Mini-Clip kit for Mossbergs line of their pump models for the Hater Tots. Not semi compatible. All of this is what makes the V3 platform so awesome. Recoil springs IN the receiver, only the gas pistons external. I love it. I did look at the 940 and it could be made to run shorter if I could get to the gas ports. Go here to see a breakdown. https://thebiggamehuntingblog.com/mossberg-940-pro-field-review/ Taper of the barrel prevents moving the barrel ring because the piston would hit the barrel. Not a candidate for shortening the gas system but maybe an inch. Piston only travels 5/8 of an inch. You might get the barrel to the length of the mag tube. That would be it with the 940. Quoted: Quoted: Mossberg now has a semi- Shockwave, and some folks call the 12 ga mini-shells "Hater Tots". The Aftershock? Not sure if this is the model semi auto you we're referring to but it's the newest out by Mossberg. The new 990 is a decent piece. They offer the SBS version as well. Don't know if it's out yet. That functions pretty well and makes it more economical to build. I'm not a real fan of the recoil (action) spring going around the magazine tube unless its a 3 round tube. Means everything is closer to the receiver. My issue is (you probably already figured it out) it keeps you from making it any shorter. The action spring, along with some other parts, occupy that area where you need some space. On the 10" Remingron 1100 I did, I shortened the action slide, lightened it, moved the barrel ring and gas ports but no spring to mess with. You would also need to move the gas ports closer to the chamber. Lots of work and other modifications needed. The barrel ring looks to be around the 12" mark. Gas ports are there. OPSol Mini-Clip kit for Mossbergs line of their pump models for the Hater Tots. Not semi compatible. All of this is what makes the V3 platform so awesome. Recoil springs IN the receiver, only the gas pistons external. I love it. I did look at the 940 and it could be made to run shorter if I could get to the gas ports. Go here to see a breakdown. https://thebiggamehuntingblog.com/mossberg-940-pro-field-review/ Taper of the barrel prevents moving the barrel ring because the piston would hit the barrel. Not a candidate for shortening the gas system but maybe an inch. Piston only travels 5/8 of an inch. You might get the barrel to the length of the mag tube. That would be it with the 940. Well, that's a shame, especially since Rem Arms is all but out of business for the moment. Thanks for the explanation, and excellent work above. |
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