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Modified M38 bolt.

Mauser bolt modification

Spend any time exploring gun forums and corners of the internet dedicated to military surplus firearms, and you’ll quickly encounter the opinion that Mauser’s bolt design is the standard by which all other bolt actions should be judged, and that most subsequent “improvements” were purely cost-saving modifications.

As a big fan of the small-ring Mauser variants, especially in the super-accurate Swede, it was only a matter of time before I started pulling apart my Husqvarna M38 to see what I could improve. Most Mauser bolt mods are bent handles to allow for scope clearance – something which has been covered ad nauseam all over the place.

So, instead of going over the same ground about oxy-acetylene torches, vices and hammers to get your military Mauser into sporting condition, I’m instead going to look how to reduce lock time by shaving some material off the cocking piece and firing pin. As always, remember that modifying your firearm is dangerous/irreversible/stupid, etc.

What is lock time?

Lock time is the minuscule period of time between when you pull the trigger and when the firing pin crushes the primer to set off the powder inside the cartridge. In other words, how long it takes the firing pin to travel to the primer from the time it is released by the pull of the trigger and the disengagement of the sear. The term lock time comes from the age of muskets – flint locks and wheel locks – the time it it took for the lock to work.

Essentially, the longer the lock time, the more likely it is that the shooter’s natural movements will move the rifle off target. The other period of time that is quite significant is how long it takes the bullet to leave the barrel, as again, the shooter can move slightly during this time.

So, naturally, it’s in a shooter’s best interests to have as short a lock time as possible. Modern bolt actions are incredibly quick compared to old military surplus rifles, and the chief ways in which lock time can be decreased are through eliminating excess material which causes resistance, friction or drag, and making modifications to the main spring, or replacing it and/or the firing pin. There are a few “speed lock” products out there, which are kits aimed to help you reduce the length of travel of the striker, and usually the trigger pull as well. Often, they will also convert your cock-on-closing Mauser to a cock-on-opening action.

Personally, I quite like the cock-on-closing action on older rifles, as it allows you to “feel” more of the chambering and extraction process – a real plus for reloaders.

Removing material

This is something you can’t afford to do wrong, especially if you’re working on a rifle with hard-to-replace parts. Fortunately for me, I had recently bought a replacement bolt due to a different issue and had some good parts on the old bolt to work with.

If you’ve spent any time on Mauser-related forums, you’ll have come across Dutchman, or Dutch. A very knowledgeable gentleman with his own website dedicated to everything Mauser. I came across one of his posts, in which he showed the modifications that were made to cocking pieces and firing pins in order to produce the bolts for the super-accurate CG63s and CG80s. With this as inspiration, I set off on my own bolt-modification adventure.

I removed the thumb piece on the back of the cocking piece to reduce weight and drag, and made the firing pin short enough to match. As you can see in the picture below, the previous owner of this rifle cut down the main spring to decrease cocking effort on the rifle, but this can lead to unreliable firing and pierced primers, so I’ll be swapping that spring for the one on the blued bolt I recently bought.

Modified Mauser firing pin.
Modified Mauser firing pin.

As you can see in Dutchman’s post, there is more material that can be removed in order to reduce friction, as he shows some rifles with scalloped bolt sleeves. Whether I attempt this or not is still yet to be seen, I’d like to see the difference this makes first before going any further. The sear engagement on the cocking piece can also be altered according to his pics, but it looks like a welder would be needed to reinforce the sear engagement section. There’s also the fact that you’ll need to case harden this section again, as a cut-up sear piece will quickly wear away, creating a dangerous firearm.

I’ve opted to leave this bit for now, as I’m planning on replacing the factory trigger with a Timney trigger in the near future. I want to see what it’s like with the new bang button, before I go and make any permanent changes.

It’s all about the looks

The flush fit of the cut firing pin is much more attractive than the thumb piece.
The flush fit of the cut firing pin is much more attractive than the thumb piece.

Well, not all about the looks, but it does play some part. I’ve got to admit, the cut down cocking piece looks a lot more modern and svelte than its military-style counterpart. I’ll take this opportunity to remind you that this rifle was not in collectors condition when I got it from the previous owner, so it is purely a project – no one is cutting up a pristine M38 here!

Another thing I wanted to do was break up the solid black of my rifle. The “new” bolt I bought had been blued and combined with the matte black paint job I did on the action and barrel, it was starting to look pretty boring. For a bit of contrast I took the un-blued extractor and extractor collar from the original bolt and added it to my new hybrid monster. The end result is a little bit of flair, with no real practical relevance. Be warned though, that while the extractor is easy enough to remove, the collar does not spring back into shape nicely for you to put teh extractor back on. You’ll need to hold it shut while sliding the extractor over – which isn’t easy without the armourer’s tools. I used a pair of circlip pliers, which while tricky to do, managed the job in the end.

The blued bolt body creates a contrast for the polished extractor and extractor collar.
The blued bolt body creates a contrast for the polished extractor and extractor collar.
JW-15 bolt with and without factory bluing.

Removing bluing from your rifle

Bluing does a couple things for a rifle. It provides some level of protection against the elements, and it helps achieve a classic styling that other coating systems can’t achieve. However, there are some situations where you might want to remove the bluing from your rifle, including polishing your steel to a high shine, or preparing your rifle for another type of coating.

You can strip the factory bluing off your rifle with a very rudimentary list of kitchen/garage supplies. Here’s a look at this simple process:

1. Completely disassemble and clean firearm

Every metal part that you are going to be removing bluing from needs to be detached from the firearm. For my last project I removed the bluing from the floor metal, trigger and bolt handle. Even if you are doing your entire rifle, it still needs to be taken down. And I shouldn’t need to say this, but make sure the thing is unloaded before you do anything.

Once you have all of your bits and pieces ready, do a thorough degreasing with brake cleaner, degreaser, dish soap and water or something similar.

2. Time to get cooking

So, there are blue removal products out there made by many fine manufacturers. You could even try sandblasting your parts if you have the equipment. However, the method I’m going to focus on is cheap, reliable and effective – and probably better for the environment too. Instead of using harsh chemicals, you can simply use a couple bucks worth of vinegar.

Most people say to just leave the parts in vinegar for 30 minutes, check to see if the bluing has been removed, rinse and repeat until done. What I like to do is to heat the vinegar in the microwave (with no metal parts in it) until almost boiling. Try not to breathe it in as you move the dish to the garage, as it’s acrid and will set you off coughing. Nasty stuff.

Drop your parts in the hot vinegar and watch as the bluing literally bubbles off of the metal in spectacular fashion. It will only take a few minutes before you notice changes in the colour of your metal. When the metal looks clear, pull it out so you don’t start it oxidising again.

If you’re doing a barreled action you probably won’t have a big enough container to completely cover it in vinegar. What you can try is wrapping it in paper towels soaked with vinegar. This may be a little slower and could require a bit of extra cleanup to get it just right.

3. Attack the metal

So now you have some bare steel completely free of bluing and rust. Make sure to thoroughly clean and degrease again, removing all traces of bluing, vinegar and anything else that shouldn’t be there. Now it’s time to pull out the ultra-fine sandpaper and steel wool, and remove all of the factory imperfections and slight bluing residue that you can spot.

It’s your call from here. Some people like to coat their firearms with ceramic or paint-on applications, while others like to try more exotic metal finishes. I’m a big fan of matte colours on rifles – usually black. For firearms that spend 99 per cent of their time on the range and seldom see adverse weather or bush conditions, you can afford to go for looks over protection.

My JW-15 which is only used at an indoor smallbore range, has had the bluing removed from the bolt handle, trigger and floor metal as mentioned above, and was polished thoroughly with autosol. I do have to make sure the humidity level in my safe is under control and that the metal surfaces are oiled when not in use for long periods, but realistically I find that the same applies to my factory blued firearms. I’ve got to admit though, that shiny metal is pretty sexy!