r/canadaguns • u/me002756 • May 31 '26
Misc Looking for guidance before using lapping compound to smoothen the action on my bolt action M77 Ruger GSR .308 WIN
Following weeks of dry-cycling the bolt (on my M77 Ruger GSR .308 WIN) hundreds of times to help 'break in' and smoothen the action, I am finally ready to try a set of dry-cycling using Wheeler 600 grit lapping compound and JB Bore cleaning compound. My intention is to help improve what was initially a surprisingly sticky/rough action from the factory (- I have no interest in aesthetics or polishing the bolt for cosmetic reasons). In terms of the smoothness of the action, when the rifle was brand new, I'd rate it 3 or 4 out of 10. After 1,000 or so dry-cycles over several weeks, I would now rate the action smoothness at about 6 or 7 out of 10. I only intend to apply lapping compound once or twice ever (and then run a set of 250 dry-cycles), to get the action closer to what I'd consider 9/10 smoothness, and then I'll continue to occasionally do dry-cycling drills without any solution applied, indefinitely.
I am new to all of this, but I did look online over several weeks for insights. I'm sharing my intentions here, seeking any advice or clarification regarding concerns or best practices, as some of the information I've seen seems conflicting or was in regard to slightly different bolt models (e.g. Ruger American bolts).
1. I intend to remove the striker assembly from the bolt, to avoid getting any compound on the firing pin or enmeshed in its spring.
One concern is that the Ruger manual cites the firing pin as a component that 'must be factory fit' and I don't want liability issues to affect any warranty coverage. I'm assuming they are referring to the installation of the pin within the striker assembly and setting the compression of its spring, and not merely the removal of the striker assembly(?)
2. I intend to apply compound (Wheeler first, then JB) to the sides and rear of the locking lugs and the full exterior of extractor, because they are what seem to principally make contact with the receiver. However, the information about this online is conflicting.
Some sources suggest ONLY applying compound to the rear of the locking lugs, while others suggest applying to the full exterior of the bolt EXCEPT the locking lugs, so as to avoid headspace issues. Additionally, from what I've seen, all sources remove the extractor entirely for the whole process, which seems counterintuitive to me because it appears to make the most contact with the receiver as the bolt glides through it.
From what I gather, it is mostly the lugs and the extractor making contact with the receiver and thereby presenting friction, so it only makes sense to apply compound there. I've also considered applying compound to the entire external body of the bolt (except the face/head and handle), but I'm weary of causing too much compound mess to be able feasibly remove all of it from the receiver.
3. With the compound applied to the bolt, I intend to dry-cycle the action 250 times, using the complete forward and backward, up and down manoeuvres to open and close the bolt.
Here again, the information online is conflicting, with some sources suggesting to ONLY open and close the bolt (move the handle up and down without cycling the action back and forth), and others suggesting to ONLY move the bolt back and forth without opening and closing the action with up and down movement of the handle.
4. I intend to do all of this on the rifle (that is, without removing the furniture and barrel and placing the receiver in a base vise). I would then try my best to meticulously and manually remove any remaining compound using only the standard rifle cleaning tools I have (e.g. patches, picks, brushes, solutions etc.).
I have seen it done both ways, however I'm weary about adequately being able to remove all compound residue from the recesses for the locking lugs inside the receiver, if the barrel remains attached. (For instance, in one source where the barrel has been removed, there's a suggestion to use compressed air and/or to boil the receiver to remove any residual compound). Yet, I do not want to needlessly remove the barrel, with Ruger also states 'must be factory fit'.
5. Before re-installing the striker assembly, I will attempt to clean the inside of the bolt itself (since there are cutouts through which the compound will likely enter), using the standard general cleaning stools I have, and possibly compressed air, if I get access to equipment. I'm hoping this will be adequate.
6. Finally, after cleaning the receiver and bolt and after removing any residual compound, I will re-lubricate the bolt and action.
I am very much a novice, to firearms in general and to firearm maintenance especially, so I sincerely appreciate any corrective feedback or advice.
As mentioned, I have already seen improvement in the smoothness of the action through dry-cycling alone, and my goal is for marginal improvement from lapping. I am confident that without applying compound the smoothness may get closer to 8/10 with time and continued cycling, but I'd like to help my chances getting it there or beyond. That said, if there is considerable risk of damage (e.g. headspace issues or contamination due to lingering compound in the receiver or inside the bolt), or significant impact to the wear of components, or compromise to warranty coverage, I'd rather just forego the lapping process altogether and settle for 7/10 or 8/10 smoothness.
Thank you, for your time and consideration.
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u/AdditionalLoss7274 May 31 '26
An old fella once told me about the "hockey game trigger job". Take some toothpaste (a very mild abrasive) slather up the are you're concerned about, and just work it back and forth for the duration of a hockey game.
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u/me002756 May 31 '26
Wow, that's interesting... but, I'd be weary of the gunk/residue vis-a-vis the potential for improving smoothness.
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u/Foreign_Active_7991 May 31 '26
Wary, not weary bud. Wary means cautious/watchful/suspicious, weary means tired.
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u/me002756 May 31 '26
Thank you, I actually wasn't aware of this (and I am a secondary school teacher lol).
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u/Foreign_Active_7991 May 31 '26
No worries, I see the mix-up all the time on Reddit and for some reason it annoys me to an unreasonable degree 😂
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u/DougMacRay617 May 31 '26
You bought a ruger... its never gone going to be 9/10. That's custom action territory. Save your money for ammo and properly break the gun in with live ammunition
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u/me002756 May 31 '26
That's understandable. I'm increasingly happy with action and just want to push it a bit further than where it currently is. I agree that it's likely possible through more natural breaking-in.
I do not exclusively dry-cycle instead of actually firing the rifle. I also do range sessions with live ammunition, which I have invested very heavily in.
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u/Difficult_Pipe_991 May 31 '26
NO PLEASE NO NIET RIFLE IS FINE
Seriously tho you’re just gunna set yourself up for damage down the line if you’re going to use this rifle a lot, even a little of you go overboard.
Try some expensive gun greases, I forget what mines called but it mad my Franchi momentum go from 8/10 to 11/10
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u/DifficultReference99 May 31 '26
Just shoot it. Mine took 200 rounds to "feel" different. And even then i can tell the difference from a full cleaning where i grease the rails a locking lugs to when i just whipe it down and pull a bore snake. Like people said this is a mauser..it will never feel like a savage, remington or ruger ect... Practice breaking the bolt throw into simple movements.
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u/me002756 Jun 01 '26
Yeah, it's definitely getting there and I'm certainly getting better form with practice and reducing the impact of human error. (I've already put more than 200 live rounds through it).
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u/thanosReally May 31 '26
I’m not a gunsmith but have lots of experience machining and lapping. Be careful with lapping compound as it tends to bed itself into the softer of the two metals being lapped. Getting it out after is near impossible (learned that lesson the hard way). You may be better off with emery paper for this reason. You can use a thin layer of Prussian blue to see where contact is most severe and hit those spots.
Either way you go, 600 is very fine and you won’t remove much material, and for that reason I’d say go for it.
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u/me002756 May 31 '26
Do you have any experience with JB compound?
It is labelled as a non-embedding cleaning compound and not a lapping one, and it appears to be much less dense. Perhaps, if I am still dissatisfied after the summer months, I will try it with JB bore cleaner alone and not any lapping compound.
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u/thanosReally Jun 18 '26
I do not, I work mostly with diamonds and industrial lapping compounds. A quick google says that JB is finer than jewellers rouge, which is hella fine. You'll likely make no progress at that rate.
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u/catchinNkeepinf1sh Jun 02 '26
After 10+ years, my 308 gsr is now a 7-8/10, the 223, which i dont shoot or carry as much is still a 6/10. I think the stainless action is just a bit more rough than my blued mk2.
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u/CanadianBoyEh May 31 '26
When you say dry cycling, do you mean fully dry? No lube on the bolt body or grease on the lugs?
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u/me002756 May 31 '26
I mean 'dry' in the same sense as 'dry-firing', which I take to mean without live ammunition. So I am specifically referring to just working the action either with snap caps or nothing at all.
Every week, I do this dry, as in without lubrication. Once a month (in place of one of the weekly sessions without lubrication), I do it with lubrication using oil and grease.
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u/CanadianBoyEh May 31 '26 edited May 31 '26
I would try this a lot more often than just running the action with no lubrication. Lapping compound of any kind is likely to do a lot more harm, than any good at all.
But the GSR action is also a workhorse action that wasn’t designed/built for absolute smoothness. If that’s what you’re after, you need to look into a custom action.
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u/me002756 May 31 '26
Yeah, I have seen that video and that's what I do once a month and occasionally at the range, too. However, I was ideally looking for a more permanent solution so as to 'waste' less lubricant. (It is hard to come by such materials, where I live).
My assumption is that lubricating it only helps temporarily until the lubrication has worn off - is that correct?
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u/CanadianBoyEh May 31 '26
Yes, lube/grease will eventually need to be cleaned off and redone.
Your action will most likely smooth out a touch more with firing and more cycling, but you’re probably close to as good as it’s going to get. Again, if you want that buttery smooth bolt feel, custom action is the way.
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u/buji8829 IBl Precision May 31 '26
Man I do not recommend going after this with lapping compound. Theres so much potential for this to go wrong. The Ruger M77 is based on the Mauser action. In my experience that isnt the smoothest action in the world. Id leave it, and enjoy it, over time (as you have done already) the action will wear in naturally. Going after it with lapping compound is just asking for problems IMO.