We mentioned the possibility of an article covering basic rifle maintenance in the April issue of Target Shooter and enough of you responded to make it a reality, so here goes.
We’ll keep it simple and restrict it at this stage to the centrefire bolt-action rifle and we will start with the bolt itself.
The bolt is a key part of our rifle. Not only does it close the breech, sealing the pressure-chamber, it also extracts the fired case and provides ignition via the firing-pin striking the primer. It is this latter function that concerns us most when it comes to maintenance.
Lock-time - the time taken for the firing-pin to strike the primer after we have pulled the trigger - is measured in milli-seconds. Even though the lock-time is unimaginably small, movement of the rifle can occur in this time-period and if it does, accuracy will obviously suffer. Clearly, a fast lock-time is desirable - even more desirable with a hand-held rifle, where movement is more likely to occur.
A number of factors will influence lock-time but the one that we can do something about is the firing-pin/spring assembly. But first, let’s dismantle our bolt. Most bolts are designed to easily ‘field-strip’ and even if our featured bolts are different from your rifle, you’ll be surprised what you can find on the internet. (In less than a minute I had a YouTube video of a Mauser bolt strip).
The spring assembly usually screws into the main bolt-body (e.g.Remington, Winchester, Stolle) but some bolts employ a bayonet-style engagement (e.g. Howa, BAT) or even a screw-on cap (e.g. Savage, Barnard, RPA).
The picture above shows a few types – from the left: Remington, Winchester, Howa and Barnard. We will concentrate on the Remington as it is one of the most popular and I just happen to be trouble-shooting a light-striking problem with one.
Using a suitable stripping tool, we can compress the spring and easily unscrew the firing-pin/spring assembly. We now have two parts – put the spring assembly to one side and we’ll deal with the bolt-body first.
The problem here is the likelihood of crud accumulating deep down inside the narrow passage that guides the firing-pin. Gases blow back through the firing-pin hole and if you’ve ever pierced a primer, this is where the small metal disc ends up. An aerosol of auto carburettor cleaner (Halfords) is useful here . Spray inside the body and swill out the crud. If it looks very dirty, use a pointed stick – like a kebab stick with a cleaning patch attached. Shine a torch inside to ensure it’s clean. Whilst you’re at it, spray the bolt-face with the cleaner – particularly around the extractor and ejector pin. Depress the pin a few times to make sure it’s running free. If you have access to an air-line, give it a blast inside and out and the job is done.
Now for the spring assembly. I’m intending to fully dismantle the Remington spring assembly as there is a problem with light-strikes but for normal maintenance it’s not necessary and we are simply going to clean the spring-assembly with our aerosol carb. cleaner to remove all traces of crud and grease. We do not want ANY grease or oil on the spring or pin – it will cause drag and increase lock-time! Again, dry off with an air-line if you have one. A light spray with WD40 is all we need – no oil or grease on the spring or pin please! You can put a very small amount of grease on the threads or bayonet prior to assembly.