Working on Rimfires
If your business is to survive you can never forget that you have to do more than fix guns, you have to make a profit. Working on rimfires can make this hard or impossible. Built from the cheapest of materials and many times poorly designed they can be a real time consumer for the gunsmith.
The average rimfire that is brought in for service has been shot thousands of times without cleaning and when it finally jammed the stuck round was pried free with pliers and screwdriver. The delicate feed mechanism that was formed from soft steel sheet metal or plastic now looks like it was hit by a drunk driver. All the other working parts are worn badly as well and the whole thing is a mess. Of course it didn’t cost much so don’t let the bill go over $40 without calling. Try to turn away these jobs as much as possible but some will be unavoidable. I’m not talking about Old Winchesters, Marlin 39s and Rugers here but you will quickly know which ones you need to avoid.
Make sure your customer understands you have to charge for your time and how extensive the work will be before proceeding. You will have customers that will not understand why it cost more to fix that it cost to purchase new and it is best to resolve this before investing your time and money. Yes there will be customers that have a special gun that was in the family and they want to fix it up for the grandkids or just memories but sometimes it just makes more sense to turn it into a wall hanger.
Also understand that if you do a repair on one of these worn out oldies it will be your baby from then on. The story that will be told was “ I carried to the local gunsmith and it hasn’t worked right since”. It won’t matter that you replaced the extractor last month and now the trigger is slipping, it will just be your fault you couldn’t even keep a 22 working. Remember a happy customer tells 1 and an unhappy customer tells 10!
OK you couldn’t avoid it and you have to work on it what do you look for?
Chamber damage– Make sure a firing pin that is too long or unrestrained and has not peened the edge of the chamber when the gun was dry fired. If the chamber is peened from the pin striking it has pushed up a burr into the chamber and will not be able to extract when it fires. If you cut this burr away the recess it leaves will be behind the case rim where the firing pin hits and the rim will not crush the priming compound. Better to iron out the burr with a chamber iron or a smooth tapered pin which will push the metal back into the recess formed from the strike of the firing pin on the chamber edge. Look at the chamber itself and a fired case to determine if the chamber has enlarged or swelled. Make sure the barrel has not slipped forward in the receiver and increased headspace .
Extractor– Check for wear or breakage. Maybe reshaping will improve functioning. Make sure it doesn’t catch on the chamber recess and its movement over the cartridge rim is without problems.
Feed mechanism or throat–See that it releases the cartridge at the correct time in the cycle and has not been deformed. Make sure that the cartridges are moved out of the throat and into the chamber without undue pressure or deforming the bullet. Remember it is a rimfire and can fire when the bolt strikes the rim to feed it into the chamber so proceed with caution!
Firing pin– Make sure the tip is correct shape and protrusion within normal limits. The best design will strike just inside the rim and not on the edge. This probably won’t matter unless it is a target rifle as long as it has sufficient force to crush the rim. If the rim is not supported by the chamber the pin strike will not be able to get good ignition. Dirt and powder residue accumulate in the firing pin recesses and cause light hits and misfires.
Trigger– Dirt and wear are the problems here. Trigger and sear notches wear down and need to be recut. If the original part was case hardened then your repair will not last unless you restore the surface hardness by carburizing and heat treating. Always check safety function when doing any work and make sure the gun will withstand several taps with the plastic hammer without firing. This can simulate the gun being dropped.
Magazines– Always a problem. Removable clips are easily lost and replacements are hard to find. Tube magazines are harder to lose but the internal springs break and rust and small dent will impinge on the follower and prevent it from working. Replacements are best but rebuild kits are available from Brownells.
Ammo– Lots of variation in ammo. Make sure the customer understands how to let the gun tell him which one it likes. This is easier than the other way around. Standard velocity, high velocity and hyper velocity all perform differently.
Remember all guns have the same basic cycles. Loading, feeding, firing, extraction and ejection are all required to be flawless. A good understanding of the cycle of operation and a thorough examination of the action will usually show what needs to be done. Work through each process and test fire thoroughly. Regular church attendance will also help ( at least with the cussing)