GunLab

AR-180b upper receiver

Here At Gun Lab we actually have a number of projects going on. While we are waiting for our heat treating to come back for the VG1-5 and AR-180b parts we started on the AR-180B upper receiver. This receiver is design to fit on the Nodak-Spud lower as well as the AR-180B lower and the original AR-180.

The project was started July 20th when a friend sent me a original flat for the AR-180. That evening I sat down and started the solid model drawing for the upper receiver. It was not a priority project here and was put on the back burner until the projects on the mill were completed. However, by July 30th I had completed the solid model and had completed the first set of basic modelling for the stamping die.

This first picture is of an original AR-18 flat that has had ribs pressed in.

This picture shows what it would look like after the next stamping. The basic shape is cut out.

The next step that was performed was to bend the bottom tabs.

The next step was then to punch out the ejector port and cocking handle opening.

With the advent of technology we have made a few changes to the process in which this part will be made.

In looking at an original AR-180b upper you can see a few of the manufacturing changes. Looking at these pictures and at the actual part you can see that a laser cutter was used versus stamping them out. The cost difference is huge.

What we have done is drawn up the receiver then changed it into a flat design then had that laser cut out of the proper material and thickness of sheet metal

Next we started working on the stamping design.

Once the basic design is completed we start working on each component of the design and changing the parts and assembly as we go along. Finally we come up with a working model.

Then every part and component is accurately located and attached.

Down to the pins and screws.

Once this is done we start making each of the individual pieces. Starting with the basic stock.

To the final products.

The next step and post will be the assembly then off to testing.

This is were we stand now on 8-17 and starting from 7-20. Less then 30 days from concept through design and modeling to programming and machining.

Not bad.

MP-44 trunnions update

We finished the first 6 test sample MP-44 trunnions to the buyer. This is an update report on the product. At the time we made these we had no flats to test them against so certain measurements could not be verified against an actual matching part. This lead to a couple of minor dimensions that would have big effects.

The first in the button hole that is one of the points that a sheet metal pressing sets into the trunnion properly. The hole dimension was correct, however its position was off by a very slight amount.

A .5mm in one direction and a 1mm direction in another. Small but important. Now with the solid models changed this will no be a problem in the production run.

The second problem was one of our radius was off. This radius allowed the flat to set next to the trunnion.

As you can see in the picture the radius is incorrect and not allowing the flat to set properly to the trunnion. Most likely this was a file and fit part of the original manufacturing process.

This is what it should look like.

The remaining test pieces will be corrected and sent to Pete to test prior to making the final production run.

Some of the differences that we have come across that need to be addressed when reverse engineer a part. What are the tolerances that we have to deal with. An example of this is the trunnions that we are working on. We just receiver a second cut original cut trunnion and have found the following differences. First with the original trunnion that we received there is .010 difference in parallelism between the two sides. the width difference between the first trunnion and the second one is .015 measured over the complete part in both cases. Now between our part and the first one that we started with we found our parallelism to be .003 and the difference between the two parts .003. So now the question is what is the max width. Are we over because the first part we tested was at max or are we in spec. The next step is to put the part in a receiver and check it out.

Reverse engineering is a great deal of work. Here at Gun Lab we do a large amount of it ranging from simple to almost impossible projects. In fact we currently have one our plate that has taken 2 years to get to basic drawings, now comes the hard part of checking it against every other component. Just to grasp the project not every minute has been spent on it and lucky the owner of that project is not driving me crazy and understand the complexity of the task he is asking. However it will be perfect when it is done. Everything has to checked, re-checked and then checked again, not an easy task and sometimes very frustrating but in the long run worth it.

Gun Lab update

This is an answer to a friends question about a particular project.

It is good to always keep checking with me. Things can get a little hectic around here. This is the status of the projects here.

1) the MP-44 trunnions test pieces have been completed and sent to the buyer. A few changes need to be made and we are correcting the drawings now.A post coming up about that next.

2) I hope to have the parts to fix the wire edm in this week and have it back up and getting it operational, this is for the mag wells on the AR-10.

3) we are finishing the tooling for the VG1-5 project so spot welding can go on in mass next week. While on the subject of the VG1-5 a new trigger guard stamping die has to be made, to look more like the original one. Still waiting for the heat treated parts to come back. The parkerizing set up is ready to start parking parts.

4) The cetme receiver has been solid modeled and the stamping dies are currently modeled as well, need to finish up the final oddities.

6) The AR-10 lower receiver has been modeled and half of it has been programmed to machine.; The work on the AR-10 lower will start again as soon as I can get the VG1-5 off of the HAAS machining center, need to change all the tooling out to aluminum cutters.

7) The AR-180b upper receiver stamping dies are 98% complete and hope to have them finished tomorrow. We are still waiting for the parts to come back from heat treat for this as well. Then we will start parkerizing them also.

So far That is about it. I am still working on the cnc router, made a new panel this weekend.

Chinese pistol

Last week Ian from Forgotten Weapons stopped by the house to borrow some equipment for an up coming video and he brought me a surprise. He had won at auction some Chinese pistols and had a few extras. So some horse trading perused. For some strange reason I just had to have this early Chinese hand made pistol. There was no magazine and it was missing the grips but still in good condition. This pistol shows to what length people will go to to have a weapon. The entire pistol looks to be made with hand tools, ie. chisel,file and hand drill. It is an interesting weapon so lets take a closer look at it.

The first two views are the completed pistol in a right and left view.

These next two pictures show it field striped.

You can see the chisel marks on the frame where the metal was cut away and filed to make the grip openings.

The trigger bar and disconnector looked like they were beat out of what ever they could get and then filed.

You can see the chisel marks in the slide grove.

The magazine catch is also missing, but it too was also chiseled out.

A close up of the hand made screws

a top view of the frame showing the barrel notches and the spring grove.

Close up of the barrel groves

The slide

A close up of the block, look at the chisel marks here.

The barrel was also hand made

The recoil spring and guide.

I am not sure what caliber this pistol is in. The magazine well looks to be large enough for 7.62×25. A caliber way to powerful for a basic blow back pistol.

This pistol is an interesting design and build.

Weekend update and the fun of machining

Nothing really exciting to report. I spent the weekend machining large pieces of metal into smaller pieces. We have shipped the test MP-44 trunnions to Pete and while we are waiting for his report back we are filling our time working on making stamping dies. In this case all the pieces are sized and we have started machining the the individual pieces for the AR-180 upper receiver stamping dies. A quick look at the solid model of the stamping dies

This is what it looks like in the making phase. Here are a few pictures of the top and bottom plates being sized up on the Allan Bradley cnc mill. A great deal of the die steel is not heat treated and just basic run of the mill scrap steel. These sections came from torch cut trash steel from different job sites. You can see the type of edge it has and need to be cleaned up and sized.

A close up of the edge. This will take a great deal of work to clean up and make useable.

So Saturday and Sunday I got to do this. A basic program was written to reduce and clean up the edges 0.030″ at a time until they were clean up.

The two bigger pieces were machined. The top and other edges will be cleaned up on the HAAS machining center.

All three of the pieces ready to continue on to the next phase.

The actual heat treated press areas are also machined to size and we have started on the forming portion of the dies.

Unique 22 single shot rifle

Our friend in Germany, Axel, knows that I am always interested in weapons of all styles and calibers so with today’s e-mail came some interesting pictures. I have a number of different types of single shot weapons and find them all interesting. Here is one that I have not seen before, not that that means much. It is a single shot with a lifting breach action.

Right side view of the rifle.

Left side view. Interesting shape for the receiver.

Close up of the receiver.

The action open. Lifting breach block and a very simple extractor.

Interesting front sight.

FN-Fal 7.92×33 second version

With the last post we made on the 7.92×33 FN-FAL we showed a FAL that had a new ejector block and magazine made to allow the rifle to shoot 7.92×33. This post will show a different approach to reach the same conclusion, shooting 7.92×33. This series of photographs comes from another friend of Gun Lab and how he converted his rifle to use MP-44 magazines.

This version the owner cut down the receiver by 0.900 and welded support plates to enlarge the magazine housing.

He also put a side rail on it for a scope. You can also see the flapper magazine release for the MP-44 magazines.

A close up of the magazine release . IMG_0575c

When the receiver was shorten then the bolt and bolt carrier also had to be shorten as well.

Reference pictures to show the length of the new bolt.

A view of the underside of the receiver to show the magazine well.

A series of pictures showing the size of the new bolt carrier.

A great deal of work went into building this rifle.

The loss of an interesting web site

It appears that “DIY self defense”,(http://diyselfdefense.tumblr.com/) has gone off the air. It was a great site and he had cool stuff that he found and posted. It and Improv Guns (https://homemadeguns.wordpress.com/) were the only sites that dealt with home made firearms.

I have always found it interesting what people can come up with when weapons are outlawed by their government.

I will miss his site.

Parts wanted and for Sale!

Looking for G-43 fire control parts. Hammer,trigger,sear. This is for one of the projects we are working on. A friend of Gun Lab has helped out with this. Thanks

Continue reading Parts wanted and for Sale!

FN-FAL in 7.92×33

In my list of want to do build projects building an original FAL is on the top. The very first FAL ever built was in 7.92×33 and was slightly different then the current FAL that we know today.

This rifle is missing and all that is left of it are the pictures you see here.

These picture are from the FAL book published by Collector Grade Publications. If you are into the FN FAL rifle this set of books is a must have.

This is Pete’s , a friend of Gun Lab, version of a 7.92×33 rifle. His solution was to put in a new ejector block of his design with a spring loaded ejector. Then remove 0.900″ from the magazine to fit the 7.92×33 round.

A side view of Pete’s rifle. Notice the larger then normal ejector block.

The magazine actually looks like the original.