Building A Mauser Sporter, Part 4
September 23, 2010
Installing A Trigger, Safety & Trigger Guard.
The author chose a Boyds adjustable trigger for his .35 Whelen Mauser conversion. It is adjustable for weight of pull, sear engagement, and overtravel. Note that this model does not have an integral safety.
Mauser rifles have been converted to sporters for civilian use almost as long as they have been used by the military. In the U.S., sporter conversions reached their peak in the 1950s and '60s, driven by the major influx of imported surplus military Mausers following World War II. Sporterizing Mausers was a very popular activity among hobbyists and was reflected in the many how-to articles that appeared in early issues of Shooting Times.
To commemorate our 50th anniversary, we're once again converting a well-used and slightly abused 98 Mauser into a sporting rifle.
In the first three installments of this series, I examined and prepared the action; fitted and headspaced a prethreaded, short-chambered Brownells barrel in .35 Whelen; welded on a sporter bolt handle; and drilled and tapped the barreled action for a scope base, iron sights, and a receiver sight. The next step was to replace the military trigger with a commercial adjustable trigger.
There are a number of very fine Mauser triggers available. I chose a Boyds Gunstock Industries trigger. Yep, the folks who make great stocks also offer a darn nice Mauser trigger. It's adjustable for weight of pull, overtravel, and sear engagement. It comes preset with a pull weight of 3.5 to 4.5 pounds. Mine turned out to have a nice crisp pull at a little over 4 pounds, so I left it at the factory setting. Boyds offers two triggers, one with and one without an integral safety. I chose the trigger without a safety, as I intend to set up this rifle with a Model 70 Winchester-type swing safety.
I opted for a side-swing safety for a couple of reasons, though I had the option of using a more common trigger-mounted safety. The trigger-mounted safety requires opening up the stock for a lever that is mounted on the right side of the trigger. This results in an unsightly gap on the right side of the receiver tang. Also, a trigger-mounted safety only blocks the trigger when engaged, while the side-swing safety mechanically blocks the striker or firing pin. This is a very reliable and positive safety. Finally, the side-swing safety just looks nice on a conversion like this.
Rather than using the military safety, the author opted for a Wisner two-position, Winchester-style, side-swing safety mounted on a Brownells Mauser bolt shroud.
The Trigger & Safety
Installing a side-swing safety is not the easiest job in the world, but a couple of readily available products from Brownells make it simpler. I began by replacing the military bolt shroud with a Brownells Mauser bolt shroud that was pre-cut for a two-position side-swing safety made by Wisner's Inc., which is also available from Brownells. This saves a lot of work and machining. The only major work I had to do was open up the safety pivot pin hole with a #21 drill and do a modest amount of fitting of the various safety lever components.
One word of caution: When installing any trigger or safety, you absolutely must check and then double-check your work to be certain that it has been done correctly. Make sure that the gun will not fire when the safety is engaged. With the gun cocked and the safety "On," strike the barreled action with a leather or plastic mallet to jar the gun and try to force the striker or firing pin to fall. Also check to make sure the rifle will not fire after the trigger has been first pulled and then the safety released. All these checks should obviously be made with an unloaded gun. Keep in mind if there is ever an accident, the person installing the trigger and safety might be held responsible. We live in a society where people sue at the drop of a hat, so be very, very careful
The Wisner safety lever is shown mounted on the bolt with the lever in the forward, or "Fire," position.
The Trigger Guard
Once the safety and trigger were installed, I began work on the trigger guard. The Mauser military trigger bow is massive and strong, as it should be on a military firearm. However, it is anything but attractive. To make such a conversion more attractive and to give the finished rifle a more commercial sporting look, something has to be done with the trigger bow. Some folks will try to reshape the military trigger bow by using a file to make it thinner. This seldom works well. At the end of the day, the trigger bow still looks military.
I take a slightly different approach. I begin by simply cutting the military trigger bow off the guard with a hacksaw. I then flatten the bottom metal with a file to smooth it up and remove the final traces of the military trigger bow.
A shotgun trigger bow is then installed in place of the old military trigger bow. The shotgun guard is thin and gracefully shaped, and it gives the bottom metal a very nice look. I often find old shotgun trigger guards in junk boxes at gun shows. You can also purchase them from parts suppliers such as Numrich Gun Parts. If you set up your rifle with double-set triggers, most shotgun trigger bows are just fine. If, like me, you use a single trigger, you may need to shorten the trigger bow by cutting it, removing a bit, and then welding it back together.
The shotgun trigger bow I used required drilling and tapping a 1/4-inch by 20 hole for the threaded stud on the front of the bow. The rear of the bow will be held in place by a wood screw placed in the underside of the pistol grip of the stock. Later, when next installment and inletting the tang of the trigger bow, I'll take care of that part of the installation.
With a new trigger, safety, and trigger bow installed, this ol' Mauser is beginning to shape up as a pretty nice sporter. In the next installment, I'll fit and bed a nice Boyds walnut stock. Until then, good luck and good gunsmithing!
Rather than using the military trigger bow, the author replaced it with a modified shotgun trigger bow. The military trigger bow was cut off with a hacksaw, and then the trigger guard base was smoothed with a medium-cut file.