M1903A3 Build Log

[tinydata]

Alright, so I've finally decided to proceed with a BAR-10/VSR-10 to M1903A3 conversion.

My thanks go out to 2ndBat and Roma, who provided inspiration and a lot of help with their guides. I simply want to put another guide out there for prospective builders to have access to.

I will be doing a build that involves as many cosmetic modifications as possible. I have enlisted the help of a Vietnam vet who made worked on Hueys and now does car restorations.

I chose the M1903A3 as the parts are easier to find and the sights are easier to mount.

I'll break the project down into four parts:

I. Wood furniture
-stock and handguard
II. Receiver group
-rear sight
-magazine cutoff
-trigger mechanism
III. Bolt group
-safety
-firing pin and striker
IV. Barrel group
-front sight

The goal is to make the top look like the bottom:


Step one is obtaining the parts. I ordered from Numrich Gun Parts and Sarco. Both are good companies that have a HUGE selection of M1903 parts.

I bought:
M1903A3 S-stock
M1903A3 handguard
M1903A3 front sight base, blade, and pins
M1903A3 rear sight assembly
M1903A3 trigger guard/floorplate assembly (stamped)
M1903A3 buttplate w/ screws
M1903A3 rear sling swivel w/ screws
M1903A3 lower band, sling swivel w/ screw
M1903A3 stacking swivel w/ screw
M1903A3 upper band w/ screw
M1903A3 striker assembly
M1903A3 bolt and safety sleeves w/safety assembly
M1903A3 magazine cutoff w/ screw
M1903A3 handguard ring
30 inches of 1/2inch copper pipe (for outer barrel)

The total came out to around $280, excluding base gun.

Step two is refinishing the wood furniture. Unless you buy reproduction stocks, your wood parts will be at least 67 years old. A lot of the time, they'll be coated in dust and look a little beat up.

Here's what you need to fix that:
-Grade 0 steel wool
-Quadruple aught (0000) steel wool
-boiled linseed oil

First, use the 0 steel wool to gently scrape off as much crap as possible from the stock. Then use the 0000 steel wool to finely smooth the wood and clean out any small imperfections.

After making sure the stock is clean, grab a paper towel and soak it with linseed oil. Apply the linseed oil generously and allow it to dry.

Linseed oil was used on all U.S. weapons with wood furniture. In the case of Walnut, linseed oil strenghtens the wood, provides moderate waterproofing, and darkens the stock. It is a MUST to make any WWII rifle come to life.


This was manufactured in WWII, but it looks brand new!

Enough for today, more to come soon

[Schmozilla]

very cool. Hope it comes out excellent Good Luck! ~Schmozilla

[tinydata]

Update: Got the wood furniture fitted last night. It is not the cleanest job, but it was pretty straightforward.

I'll have pictures up soon

[tinydata]

I've got the stock, handguard, and metal hardware all fitted and ready to go.



The first step was, of course, to cut the stock to fit the BAR-10 action. This is actually extremely easy if you have two things: a table vise and a router.

With a router, cutting the action space out is like cutting soft butter.

To do the magwell, first mark out the approximate area that you'll need. Then drill a hole, expanding it slowly with the router until you have a rectangular opening.

Then, cut your BAR-10 outer barrel with a saw/dremel right ahead of the hop-up. BE CAREFUL- do not cut the hop up arm or you'll need a new one. Then use electrical tape to fit a 1/2inch copper pipe around the inner barrel and cut it down to size.

The handguard is a different story from the stock- sand, sand, sand! Basically you have to hollow it out to fit. Make sure your action is completely seated- this means that you don't have to cut out as much

To do the triggerguard, you need to first cut out the rear bulkhead in order to accommodate the trigger mechanism. After this, cut the front portion of the triggerguard to make room for the BAR-10 magazine. Finally, enlarge your trigger hole to fit the BAR-10 trigger, which is a bit fatter than that of a real M1903A3.

Buy a longer screw to hold the rear receiver in, then drill a hole in the triggerguard to fit another screw to hold the action in.

After painting the outer barrel, install the buttplate, bands, and swivels.

At this point, the M1903 is usable as a scoped A4 variant. I still have to install:

-M1903A3 front sight
-M1903A3 rear sight
-cutoff
-magazine catch (I think I'll borrow Ersatzjack's method)

[HornetWSO]

You're doing a great job! Really looking forward to seeing this completed.

[nkronsch]

Nice work, very helpful.

[tinydata]

I got the magazine catch working.

I was originally intending to use Ersatzjack's method with a piece of spring steel, but I then ran across what Sgt. Tom did with his, cutting out the original mechanism and adding it to the wood stock. This is actually extremely easy, and it works like the original because it is the original!

I really messed up on cutting the magazine well, so I think I'll modifying another M1903 stock sometime. (this one works, its just horrendous)

As of now, it is skirmishable.

[tinydata]

I got the iron sights fitted.
The front sight is simply slipped onto the 1/2inch pipe that serves as the barrel.

For the rear sight, I cut up a piece of BAR-10 scope rail and then filed the rail down to fit the sight's dovetail. That way, I have the sight aligned and level.

[Echelon]

This is awesome so far.

[Schmozilla]

Incredibly good Job!

[2nd Bat]

It really came out nice TINY. Great job!

[tinydata]

Thanks for the compliments everyone

2ndBat, I want to thank you in particular for providing the inspiration to build one.

Would anyone possibly be interested in buying something like this? I call this a "basic" model because of a lack of bolt modifications. I'd probably offer just a scoped variant.

It takes me about 15 hours to go from start from finish but I'm confident I can get it down to 10-12. I now know what to cut and how much. I've also invested in a set of wood files so I can also do much higher quality work.

The next step from here is getting my bolt parts machined to fit the BAR-10 cylinder. After that, accuracy and power upgrades.

[cairo1]

sharp work mate. keep it up.

[tinydata]

So I decided to cut another stock, this time more cleanly. This one had a crack and a chip, but there's a way to fix that.

So, the easiest way to do it is to first mark the area off with some sort of tape. After that, expand the magwell with a hand router (seen in the picture) starting from the front triggerguard screw hole.




After getting the rough cut done, use wood rasps to carefully expand the magazine well. You want to use your tape markings to get slightly under the size of the magazine so you don't screw up with the router, but you can always slowly cut away with the rasps.

The result is a much cleaner cut:


To make indents for gripping the BAR-10 magazine, simply use a sanding drum or router tip to slowly cut the indents.

Earlier, I mentioned repairing chips. Take the sawdust from your earlier cutting and sanding and pack it into the damaged area with some Elmers wood glue. After packing it tight, let it dry and then use some extremely fine sandpaper to smooth it over. Darken it with some linseed oil and it will just look like a piece of stock that got stained. Adds character if you ask me!

[jettalewis]

I love the work you are doing on your 1903 and let me tell you how I did part of the cuts. Instead of using a router I purchased a 3/4 inch wide belt sander from Harbor Freight. It did an excellent job and only used two belts for the entire job. It is the perfect width to cut the mag area and it dead fits the area for the trigger assembly to fit in. Very little chisel work in these areas All of the unneeded wood was cleared out in a matter of minutes wiht a particularly good looking finish to the job. It might not help this job, but there wil future jobs.

[HornetWSO]

Aug 19, 2011 23:05:33 GMT -5 jettalewis said:

I love the work you are doing on your 1903 and let me tell you how I did part of the cuts. Instead of using a router I purchased a 3/4 inch wide belt sander from Harbor Freight. It did an excellent job and only used two belts for the entire job. It is the perfect width to cut the mag area and it dead fits the area for the trigger assembly to fit in. Very little chisel work in these areas All of the unneeded wood was cleared out in a matter of minutes wiht a particularly good looking finish to the job. It might not help this job, but there wil future jobs.

Jettalewis - great tip, these are the kinds of insights that really can help others out!!

[tinydata]

Finally got to use the M1903A3 in a game. I went up against M4s, AKs, an M60, and still did well despite having to stick to 30 round magazines and a bolt action.

Needless to say, I'm very pleased with how this turned out!