700SPS Centerfire Rifle Accurizing – Bore Inspection and Lug Lapping

HomeContentEquipment700SPS Centerfire Rifle Accurizing - Bore Inspection and Lug Lapping

With Nathan Foster’s ‘Bolt Action Rifle Accurizing & Maintenance‘ in hand, I started the first step in preparing my new centerfire rifle Rem 700 build. First up was an initial inspection of the rifle bore and action and testing that we had good, even lug engagement.

Bore Inspection

It’s dangerous to assume that a brand new barrel is going to be sound and of optimum quality. Especially for mass produced centerfire rifles. Anyone involved in an engineering or production process will know it is easy for something minute to effect a run and how easily, in reality, it is for one or two barrels to slip through the QA process before these issues are identified and rectified. So, it becomes imperative that one of the first things you do is check out your new barrel for any obvious issues. A damaged barrel is going to kill any chance of centerfire rifle accurizing early on.

Nathan stress this importance – so first of the block, was a flashlight and a macro lens (a magnifying glass is another good option) to check out the state of my new barrel.

Realistically, most of us don’t have a borescope at home. Maybe one day. But what this practically means is we are limited to inspection of the crown and the bore area just in from there.

The camera was struggling to get a decent shot this evening, but primarily we are looking for marks in the lands and grooves. These are caused by part of the manufacturing process, and depending on their nature and severity can sometimes be corrected in the break in procedure.

I wasn’t able to spot anything major in the process – as should be the case with most new rifles – but it’s not unknown.

Lug Lapping a centerfire rifle

The second step of the ‘pre-checks’ for centerfire rifle accurizing was to establish the bolt’s locking lugs even contact. Correct lug alignment ensures proper support of the cartridge during firing. Again, not something that should be assumed correct.

The testing procedure is simple. Draw on the back edge of the lugs with a marker pen of some kind. I just happened to have red handy. Put the bolt in and work the action a couple of times. If one of the lugs has the marker pen rubbed off, but not the other, then you have lugs which need a bit of work.

The next step was pulling the action out of the stock and having a quick check everything was as it should be. I knew the stock was light, but I was interested to see what it looked like underneath. Hello, Honeycombs!

I can see why it’s strongly suggested you do something with the standard SPS stock. It’s light and hollow. Not exactly the best platform for a Long Range Rifle Accurizing project.

Stock and Trigger

I will be stabilising and then bedding the plastic stock of the SPS centerfire rifle. While many people do replace them, I have read that by using Nathan’s stabilising and bedding compound you can achieve a good level of accuracy with the stock, stock. It’s also a cheap stock to do my first bedding work on – if I cock it up totally, then I can just get a new stock without breaking the bank.

While I could just stabilise and bed the stock before shooting – I am going to do some before/after tests – I am interested in seeing the difference it makes to a centerfire rifle.

Kerry Adams
Kerry Adamshttps://thebloke.co.nz
A constant learner with an inquisitive mind, Kerry created The Bloke as a way to share what he was learning from the community of experts he found himself surrounded by. Precision Shooter and GunSafe soon followed. Somewhere along the line, he picked up one or two things himself. But don't call him an expert.

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