Target Sports

GALLERY RIFLE: WINTER TUNE-UP

Created on 29th May 2009

Part 2: the trigger unit by GWYN ROBERTS

TO ME, the standard Ruger trigger unit and some ‘drop-in performance' trigger kits feel rather rough, almost as though some sand has found its way into the works. Trigger pull can also be on the heavy side, often being 2.5lb or heavier pull weight. This is mainly due to the finish of the individual parts, in combination with the actual design of the unit and the way it functions. Here are a few ideas that I sourced from various shooters that will, hopefully, improve the feel and functioning for anyone using standard Ruger parts.

First of all, having already made absolutely certain that the gun is unloaded and safe, completely disassemble the unit, leaving the safety plunger in place. Then, thoroughly clean inside the housing, making sure you get into all of the corners and hard to reach places. A can of #WD40 with the narrow red pipe that comes with it is ideal for this purpose. Clean off all the individual components thoroughly, then lay them out and check closely for any obvious signs of binding or damage.

Top end parts

Starting with the components near the top end of the unit, make sure that the ejector is a reasonably tight fit inside its slot so that it doesn't move around during cycling, as this will improve ejection reliability. The first thing I noticed on this unit were signs of the magazine plunger binding on the inside edge of the automatic bolt release (ABR). As the ABR isn't retained particularly securely in place inside the housing, it can sometimes bow out slightly, causing the plunger to lock up against it, which prevents you from inserting a magazine into place. You may also find that you have to push the ABR back in flat against the inside of the housing, in order to depress the plunger when fitting the trigger unit back into the action. A simple fix is to file a reasonably wide groove along the contact line, then smooth it down with a piece of wet and dry paper or a sanding block. Once this has been done, you should then round off the edges around the ABR with a stone or file so that it does not bind against anything inside the trigger housing. Finishing off with a rubber sanding block will remove the rest of the blueing, before a final polish on a polishing wheel.
Anyone with a standard bolt release fitted can simply file out the heart-shaped hole, smooth the edges round, and save themselves £12 or more, rather than buying one that has already been modified. A slightly concave shape will give better results, although once the point is flattened off you should refit it and try it first, then make small adjustments until it functions 100% every time. It's a simple modification, but a very helpful one during position changes such as the ones required in the 1500 match.

The next step is to check around the edge of the plunger, removing any burrs you may find, and then do the same to the recess that the plunger fits into in the trigger housing. This area usually has quite a rough finish to it due to its casting process, and using some fine wet and dry paper will give it the desired finish. This black unit shows where the small protruding pin at the rear of the magazine has been binding during magazine changes, because of the additional layers of paint that have been added. Careful removal of the excess paint and polishing in this small area will help the magazines to be inserted and released more quickly and easily.

The hammer spring strut can be improved by stoning or filing along the edges, then rounding off the keyhole-shaped end before being polished. Taking the shoulder off the trigger plunger on a wheel grinder then polishing it up will help improve its rearward travel, as will installing a lighter spring. Make sure, though, that it has enough power to reset the trigger after each shot, or you'll end up with a single shot rifle.

Trigger release

Ruger triggers are not renowned for having a light release, and taking a close look at the finish on the hammer arc and sear will reveal why. When stoning or filing hammer parts, great care should be taken not to remove too much metal, otherwise you will remove the hardened surface. This could lead to the softer metal underneath wearing over time, which could mean functioning problems in the future. However, simply removing the burrs and high spots through light stoning around the arc and edges of the hammer, sear and disconnector, followed by a good polish-up, will give your trigger action a much smoother feel to it, rather than the sandpaper effect of a standard trigger.

The standard Ruger trigger unit as supplied may also have a tendency to feel ‘spongy' in operation. By that, I mean that the pressure applied when squeezing the trigger doesn't always translate into the degree of movement in releasing the shot that one anticipates. There appears to be some degree of ‘lost movement', which in my experience is caused by the spring and excessive play between the sear and the disconnector. My research shows that a lot of the shooters in America are modifying this area in two ways.

The first is by forming some ‘instant metal' (found in engineering supplies outlets and car accessory stores like Halfords) onto the top of the sear as shown in the picture. You must allow it to harden completely, and then simply take a bit of time filing it down into the desired wedge shape. It is necessary to refit the sear and offer it up to the disconnector from time to time, as this will let you see the angle needed for the best fit; you are aiming to take up as much of the slack as possible while still allowing the two parts to reset properly. The other method mentioned above might be the easier option though: this involves drilling and tapping the sear so that you can Loctite a rounded setscrew in place. Once fitted and adjusted properly, you should be able to virtually eliminate any excess movement during the pull, so that it will feel like a single stage trigger.

While it may be frowned upon for ordinary people to do their own ‘trigger jobs' over here, the general consensus from shooters modifying their triggers over the pond, who have been modifying 10/22s for many years, is somewhat different! Over here we are told that the angle of the notch in the hammer is critical and can only be done with a special jig, while over there they say that it's really trial and error, as the tolerances inside each individual cast unit, parts and pins are pretty substantial. Whatever the differences of opinion, most experts agree that the angle on the sear should be left well alone, and that only the notch in the hammer should be adjusted. If attempting this type of modification, the general rules are that a small adjustment in the angle is set with the hammer held squarely in a vice so that the file ends up contacting the jaws of the vice, ensuring a square, flat cut is achieved. The new angle in the hammer notch should then be polished and the unit put back together then tested by dry firing. This process is then repeated until a good let-off angle is achieved. If this type of modification is ever performed, the following two procedures must be carried out before any live firing is conducted!

1. The hammer has to be re-hardened properly (read up on the various options of doing this) to ensure that the metal does not soften later on with use, which could lead to ‘double tapping'. It will then also have to be tidied up and re-polished after this process.

2. Perform a ‘slam' test. To do this, check the rifle is clear then rack the action, leaving the safety off and holding the barrel vertically. Hit the butt pad of the rifle firmly against the floor half a dozen times or so, to check that the firing pin does not fly forwards. If the firing pin doesn't release and fly forwards, then the rifle is safe to be used. If it doesn't remain cocked, then throw the hammer away and start again!

When putting the trigger unit back together again, make sure that the open end of the U-shaped notch that holds the hammer spring in place faces upwards as you place it inside the housing, and apply just a little lubricant to any mating surfaces or pins. Anyone using a standard steel recoil pin should replace it with one made from polyurethane, to stop excessive battering of the receiver during the cycling action.

It's also a good idea to check that the pins holding the trigger unit into the receiver are a reasonably tight fit. If they are loose, you can either make some slightly oversize ones or buy screw type ones. These are now available from KID (Tony Kid triggers), which includes two slightly oversize pins that have a Torx screw at each end so that you can tighten them up, eliminating any play between the trigger group and receiver.

Finally, it's important that every time your Ruger rifle is stripped down and rebuilt, you must ensure that you test the function of the action, safety, trigger release and bolt hold-open device before commencing any live firing.

CAUTION

Although the processes described here are not particularly complex, it is essential that anyone undertaking this (or indeed any other) work on their rifle that could affect its function only does so if they understand the procedures involved and how to perform them; they must also feel confident in carrying them out. Remember, if in doubt, seek further advice or entrust the work to a gunsmith.

GALLERY RIFLE: WINTER TUNE-UP

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GALLERY RIFLE: WINTER TUNE-UP

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