Saturday, January 11, 2014

SA Inc. M1A Upgrades

I recently got a SA Inc. M1A Standard and there are a couple of cost effective mods one can perform to accurize the platform without sending it to a gunsmith; shimming the gas system and replacing the spring guide. I ordered the Sadlak NM Spring Guide directly from Sadlak and purchased the shims from the PX on M14 Forum. On this post I'm just going to cover installing the spring guide, a very simple process that you can do without the use of any M14/M1A service tools. 

As always, safety is your #1 priority, so clear your firearm before starting. Remove the magazine (if one is inserted), retract the charging handle, inspect the chamber, release the charging handle allowing it to go forward into battery, engage the safety.

[1] Release the trigger assembly.

If placing the firearm upside-down on a table (as pictured) be sure to protect your rear sight; note the setting on your elevation drum, rotate it until it bottoms out, and then place the rifle upside-down on the working surface. You can also place a block of wood in front of the rear sight under the stripper clip guide (as pictured below) to keep the weight off the rear sight. With a solid hold, move the trigger guard backwards and up, rotating the trigger guard forward, which releases the trigger assembly.

The trigger assembly is relatively difficult to remove on my M1A, you really have to muscle it. DO NOT attempt to pry the parts with a screwdriver (although I have) or anything of the like, that's when you start making a bad situation worse. If you are having a tough time releasing the trigger guard, take a sock and thread it between the back of the trigger and the trigger guard. Take the rifle, turn it vertically, buttstock on the table or take a seat and put the buttstock on your knee, then firmly pull the trigger guard back with the aid of the sock. Do not jerk it or yank on it... insert joke. Once you pop the trigger guard out with the sock, remove the sock, and rotate the trigger guard forward by hand. 

If you do have a USGI M14 combination tool, the movement is the same, back & up. You will insert the tool (not too deep as to avoid hitting the trigger) into the hole at the rear of the trigger guard. Pictured below is a USGI M14 combination tool.

[2] Remove the trigger assembly.

Once the trigger assembly has been released, remove it by lifting it straight up and out of the stock. It should take minimal force to do this.

[3] Separate the stock from the upper assembly.

Once the trigger group is removed, the stock will easily separate from the barrel/upper receiver assembly. Hold the two sections and pivot out from the front of the firearm at the front band (stock retaining plate) and the stock ferrule. Set the stock aside and place the upper assembly on your workbench upside-down.

[4] Disengage the connector lock.

Locate the connector lock pin (circled). Moving the connector pin will disengage the connector lock, allowing you to release and switch out the spring guide. I used a small flat head strew driver to move the connector pin. You will have to push the spring guide back to allow for easy movement, but be aware, you have a fully compressed op-rod spring under pressure! The op-rod spring and spring guide should remain in position once the connector lock is disengaged, but exercise caution, possibly holding it in position.

[5] Release the spring guide and op-rod spring.

If you haven't already, grasp the spring guide and op-rod spring firmly, move it slightly back and out of position and, while still maintaining a firm grip, bring it up and forward, thus allowing the spring to fully expand without sending it flying across the room.

[6] Replace the spring guide.

The existing spring guide can now be replaced with the Sadlak NM spring guide.

Pictured above is the Sadlak NM spring guide (top) and the KMT spring guide (bottom) that came with my SA Inc. M1A Standard. The difference in volume and construction is obvious.

To reassemble, follow steps in reverse.

Final notes. Shimming the gas system is a little more time consuming, but it isn't complicated, you just need the right tools and patience. Furthermore, I'm probably not going to get around to posting how it's done because Tony Ben already created an excellent post on M14 Forum about the upgrade. I'm not sure if this is a sign of what to look for, but out the box it was apparent that my SA Inc. M1A Standard had a lot of slop in the forend of the stock by the gas system. After installing the shims, it removed all play in that area. Is this an easily identifiable characteristic of what to look for when considering shimming the gas system, maybe, but I'm by no means an expert on the platform, just pointing out my personal experience and noting a feature change. Sending a few rounds downrange will ultimately be an indication of the effectiveness of this modification. One could easily invest a lot more in accurizing an M1A, like sending it out to a reputable gunsmith for a trigger job or switching out parts with USGI components, unitize the gas system, but at this point I'm saving up for some good glass and 7.62 NATO. And I honestly don't mind the trigger on my M1A... so far, that is. Lastly, as the saying goes, "if it ain't broke, don't fix it" and I'm a firm believer in this, so if your M1A is GTG, I say leave her alone and keep shooting.

No comments:

Post a Comment