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.
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 .
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.
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.
Looking for G-43 fire control parts. Hammer,trigger,sear. This is for one of the projects we are working on.
Continue reading Parts wanted and for Sale!
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.
You can see in this picture the fit on the magazine to the receiver.
You can see here how the cartridges set in the magazine.
This his new follower
A top view of the spring loaded ejector
This photo gives you a good view of the magazine well.
A nice side view of the larger ejector block.
He converted the rifle to take a smaller hand guard .
Rick from http://ar180s.com/ dropped by yesterday and spent a few hours at Gun Lab. It was a nice visit. We both got to show off projects that we have been working on. I was able to get an up close look at his shorty project and his machined out of tubing AR-180 upper. Nice work. The shorty projects looks like a fun build. Now to go back to the salt mine of my shop for today. Looking forward to your next visit.
An interesting question was brought up by Rick at http://ar180s.com/ a while back about making new AR-180B upper receivers. The actual receiver is not much of a problem however the trunnion is. The expense of making a new trunnion would be cost prohibitive so a different solution had to be found. In this case the thought would be to do what was done, or thought to be done by Armalite and that is using an AR-15 barrel extension pressed into a new trunnion block. So looking at a AR-180B we can see what the trunnion looks like in a receiver.
Looking at the above pictures you can see the difference between a AR-180B and the AR-180 below.
The above picture shows a flush front end with the threads. While of the 180B it is recessed.
There are a number of differences. The original is forged and then machined. You can see how the boss sticks out in front of the bolt locking area. While the 180B the rear of the trunnion is flush.
The reasons for these differences is because a AR-180b does use a AR-15 barrel extension pressed in. However there are changes to the barrel extension.
In this hidden view you can see that a AR-15 barrel extension would be to large for a trunnion as originally designed for an AR-180
This is a solid view of the same model. The barrel extension would get in the way of the recoil rods.
Even reducing the diameter of the barrel extension would not be enough to correct the problem. The extension has a diameter much larger then the inside diameter of the trunnion.
This can only work if the trunnion is also re-design. This is what Armalite did for the AR-180B.
Instead of a rounded bottom they squared it off to allow more material to support the turned down barrel extension.
As you can see in this cut away the reduced size of the outer ring of the barrel extension.
In this picture you can see the hole for the guide pin on an AR-15 barrel extension.
Op 7 has been completed. This is a major mill stone on making the MP-44 trunnions. The rest of the machining will be done on the manual mill. It will be easier on the manual mill then making the number of fixtures and tooling that would be required on the cnc machining center.
This is op 7. You can see the original next to one of ours. The manual phase will add the chamfer to the groves.
You can see that the trunnions are dimensional correct
A close up of the trunnions.
A picture of all 6 trunnions completed and de-burred.
Operation 6 has been completed on the MP-44 trunnions. A couple of problems were noted. The first is the difference in length on the front of the trunnions and the second was the fit up of the locking shoulder.
This photo shows the difference in the lengths
You can see the corrected locking shoulder fit up
This photo shows where the end mill breaks during op 6 not cutting the slot for the locking shoulder.
Close up of the un-machined area
As with every part made there is always a problem lurking in the back ground. We thought that we had complete op 6 on all the trunnions only to find that on the last part the end mill had broke. This caused a cascading failure problem. The next end mill, which was a custom slot cutting tool, also broke. The program was rewritten again to correct the problem and all six parts were finished through op 6.