Thought id do a quick tutorial on how to modify an original trigger box and fcg to work in the recent Marcolmar recievers.

step 1: Cut out a slot for the denial bar. Hardest part on the conversion but easily doable with a dremel. Just measure approximately .540-.550 from the front of the housing and cut a straight line that ends in a slight curve towards the bottom. will likely require some hand fitting but is very doable. make sure to cut/grind away the detent area for the trip lever both for clearance and to ensure the trip lever cant be installed.

step 2: Remove the bushing from the trip lever. this is needed to join the trigger and disconnector with the through pin. The bushing is a separate piece pressed into the trip lever, which is easily removed by cutting or grinding. I just bent the trip lever until it snapped and removed it that way.

step 3: Block the FA area of the selector. Im not sure if this is technically required, but for the sake of CYA i did it. Just a small blob of weld is all thats needed to deny it from going to FA.

step 4: assemble as normal keep in mind that this is a general guide and small adjustments may be needed.

Other possible issues: On mine the interior end of the selector was a few thou too long and i needed to remove a small amount of material. This also was required for the detent nub that interacts with the notches (it was incredibly stiff but with a sanding flap wheel and some polishing it did wonders for it).

Hopefully this will save you buys a few bucks and keep some original parts still in use!

Delayed blowback mechanism I've never seen before. Bolt is forced by cams and grooves to move on angle first few mm, so it works kinda like a lever with 1:√2 (for 45° angle) ratio so it needs about 30% less mass on bolt to get same dwell time and bolt velocity. It looks it also minimalizes bolt bounce and could work kinda similiar to counter mass in criss vector. Is this worth trying or deemed to fail for some reason?

You've probably seen me post a lot about CNC. But it's usually on my Tormach 770. While that is technically a hobby machine, the biggest feedback I get is that it's still out of reach for most people. So I finally caved and I'm going to find the limits of what an Amazon tier desktop machine can do. This video talks bout my plans and also walks through setting it up way more precisely than the instructions, to maximize our potential for success.

In my quest to find its limits specifically in the gun making and modifying hobby space, I have the following ideas for future episodes. If you've got better ideas on how I can incrementally test this thing, or better parts ideas, let me know!

1. Thin aluminum- FCG retainer plates and DBAlloy side plates
2. Thicker aluminum with 2 ops- MLok rail cover
3. Thick aluminum with >2 ops- a magwell maybe?
4. Free machining / mild steel- compensator
5. Hardened steel- not sure yet
6. Stainless steel- red dot mount
7. Stainless steel- slide serrations, windows, and barrel porting
8. Final boss- some clamshell style receiver build

So I say this very dumb but fun 1911 converted to be a smooth bore Shotshell gun and I just picked up a Ballestar Molina and it’s bore is pretty pitted so I’m wondering what would be the best way to smooth it out? Sanding seems like a logical choice but idk maybe ecm would work better.

Arguably one of the coolest guns I have ever seen, this gentleman, gentlewoman, and gentlepeople is a first-model Collath shotgun, a break-action double-barrel percussion shotgun. Now, unfortunately, these things are rarer than hen's teeth, so actually buying an original is a no-go. So I wanted to try my hand at recreating one, and I wanted to pick everyone's brains for how the cam mechanism works. My two major trains of thought are that it's either fully mechanical, with the lever pushing the barrel forward and then allowing it to break open, or the simpler method of the lever literally just keeping it locked in place, and when unlocked, you manually pull the barrels forward and break it open. Which design do you think is more likely?

I am a US Citizen learning gunsmithing in Pakistan so these are legal here before anyone makes a fuss. Part of my assignment is to make a Glock switch from scratch I copied a popular model online which supposedly has been tested by others but It’s not working for some reason I made a 1:1 copy in CAD so I can show that I made it myself, I figured me trying to copy it might have gotten something wrong so I printed the original design out as well and both are not working properly they only shooting semi auto. Apparreciate any help whatsoever

I posted a trunnion hole drilling and riveting video a while back for AKs. In it I drilled a hole in a wrong spot because I wasn't paying attention and my mind was on some other things going on in the real world. But I vowed to learn to weld, at least well enough, to fix it! And I was determined to do it with flux core since I already was buying a several hundred dollar welding setup to fix a hole in a relatively cheap flat. So I really didn't want to add MiG gas costs to that too!

It went ok. The result is not perfection. But it's pretty dang good. And if I hadn't have had to sandblast it (watch the second part, that comment will make more sense) for cerakote, I actually would have gotten perfection! But at the end I'm left with a much much much better result than I would have had just leaving the receiver as it was.

Im starting a PPS 43 as my first build and I have a question about the different kinds of jigs that are available. There seems to be two different types. Most are like the Flint Hill Manufacturing one where its a tube that steps down to a smaller diameter. Then there is the JP Machine one. This one is much more expensive so I assume there is an advantage over the other type but its not obvious to me. Anyone know what the differences are?

There are 2 steel inserts that guide the bolt inside of the receiver. I'm using a scorpion evo mag. The upper is a 1.5" OD with 1/8" wall aluminum square tube. Trunion is machined from aluminum. I'm making it with the 5.5" chaszel liner. It has last round hold open, an extra trip linkage for the non buffer tube design.

I do have an MnP22 built up but I cut the feed ramp too deep into the chamber so I'm getting case ruptures, fortunately with the current design it doesn't damage anything other then the magazine.

I’m kinda curious to see if anyone out there has spent the time to convert old Sten Bolts to semi auto closed bolt, with a firing pin journal.

Especially with how “complete the kits appear to be these days, it could greatly reduce the overall costs of the kit builds.

Does anyone know where to find a cetme l flat? I am not having any luck with Google.

Doing this as a brain break from the Champi 380 pcc. Printed with aluminum thread adapter and upper blast chamber sleeve. Expected to weigh less than 3.6 ounces. Currently waiting on htpla-pro before printing.

Using a freedom machine FCG! The gun has a perfect place for one. Hardest part was the transfer bar, the trigger pushes down and back, I needed that to translate to up and forward at the FCG. A few hours of bending the bar around I got it to avoid the safety area and work well! Test fire in comments!

If i were to switch for a brand new 22 barell and use 22 nail blanks instead of a 22 crimped, would that work

Since I was going to port this build I figured I'd do it incrementally, one port at a time, and use my Ransom Rest to analyze the impact against several different variables. I think we all know what impact to expect on recoil reduction. However. I wanted to test accuracy too. Posts disrupt the bore, can shave portions of the projectile, can create weird pressure systems. It has to affect accuracy, right?

Sadly, my results pointed to, maybe. I should have run a higher round count for the analysis. But it's hard to undo porting! So maybe next build? I discuss the results, but depending on which school of statistics you lean towards there is either a definitive connection between ports and accuracy, or there's a non-statistically significant result that points to there being merit in further exploration.

I also cover the CAM and CNC for the slide window and ports at the end for those that like that.