Adding weight to the butt of an old milsurp

Davo308

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I have a pair of k31s that I picked up years ago, for 129ish each. They were my first "precision" rifles and I've always enjoyed shooting them.

I decided quickly to keep one stock as the original 8.8 lb K31 with open sights.

I decided make the 2nd more into a target rifle with no permanent modifications to the gun.

So the scoped gun adds about 2 lbs of weight to the middle of the rifle (scope mount, rings, scope), as well as another 4 Oz to the muzzle and about 2 inches beyond the muzzle In the form of a steel compensator.

At the butt end I have added a cheek riser and recoil pad which I haven't weighed but it's minimal.

Underneath the steel buttplate there is a hole drilled into the stock, maybe 1/2 inch plus in diameter and it's maybe 6+ inches deep. I have no idea what it's original purpose was.

I'm hoping to pack this hole with as much tungsten #9 shot as I can and then sealing the hole with duct putty.

If it ever needs to be reversed just pull the duct putty and drain out the tungsten shot.

So my questions...does this seem like a good idea?

Are there other alternatives that are better?

Will weight in the butt make the rifle ride funny on shooting bags?

At the end of the day the scoped k31 will add 3lbs of additional weight plus a compensator that is reported to cut recoil 30-40 percent.
 
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I would if you want to do it it's yours . I don't buy guns to sell so I have to do what ever it is . I want to to make them how I like it so I shoot them more often . pads , weights , scopes , colors what ever it is .
 
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I have a pair of k31s that I picked up years ago, for 129ish each. They were my first "precision" rifles and I've always enjoyed shooting them.

I decided quickly to keep one stock as the original 8.8 lb K31 with open sights.

I decided make the 2nd more into a target rifle with no permanent modifications to the gun.

So the scoped gun adds about 2 lbs of weight to the middle of the rifle (scope mount, rings, scope), as well as another 4 Oz to the muzzle and about 2 inches beyond the muzzle In the form of a steel compensator.

At the butt end I have added a cheek riser and recoil pad which I haven't weighed but it's minimal.

Underneath the steel buttplate there is a hole drilled into the stock, maybe 1/2 inch plus in diameter and it's maybe 6+ inches deep. I have no idea what it's original purpose was.

I'm hoping to pack this hole with as much tungsten #9 shot as I can and then sealing the hole with duct putty.

If it ever needs to be reversed just pull the duct putty and drain out the tungsten shot.

So my questions...does this seem like a good idea?

Are there other alternatives that are better?

Will weight in the butt make the rifle ride funny on shooting bags?

At the end of the day the scoped k31 will add 3lbs of additional weight plus a compensator that is reported to cut recoil 30-40 percent.
Why expensive tungsten instead of lead shot? Yeah, tungsten is heavy but do you think it makes that much of a diff in this application?

Also, I suggest small shot…#9 and the like…as it will be, IMO, easier to mold it in a space tightly.

Lastly, consider putting the shot into a rubber (prophylactic, right) to keep the stuff from migrating or leaking a bit.

Just my thoughts.
 
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Will weight in the butt make the rifle ride funny on shooting bags?

Unless it is a huge amount of weight that makes it overly butt heavy, I can’t see how. I’ve added weight to precision rifles a few times, using lead shot. My goal is usually to get a center balance. By that, I mean it should balance naturally if picked up by your support hand. I do not like it to be overly barrel heavy or butt heavy, making it unbalanced.
 
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Why expensive tungsten instead of lead shot? Yeah, tungsten is heavy but do you think it makes that much of a diff in this application?

Also, I suggest small shot…#9 and the like…as it will be, IMO, easier to mold it in a space tightly.

Lastly, consider putting the shot into a rubber (prophylactic, right) to keep the stuff from migrating or leaking a bit.

Just my thoughts.

I'm thinking tungsten because it's 1.7 times the density of lead and I don't have tons of room under the butt to add weight.

Secondary reason is for the fact that tungston shot is a game changer in the .410 shotgun world.

The newest Turkey guns are .410s with tungston and they are outperforming what 12 gauge turkey guns were doing as far as pattern density and range a decade ago.

I'm picking up the .357/.410 version of this soon...
 
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Unless it is a huge amount of weight that makes it overly butt heavy, I can’t see how. I’ve added weight to precision rifles a few times, using lead shot. My goal is usually to get a center balance. By that, I mean it should balance naturally if picked up by your support hand. I do not like it to be overly barrel heavy or butt heavy, making it unbalanced.

Yeah most of the 25% additional weight added to this gun has been to the middle and muzzle end.

I figure a pound near the rear will if anything help with balance.
 
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Turn a slug of mild steel to a slip fit to the wood under the buttplate, with no air gaps the weight difference is minimal and no rattling, which can be very annoying
 
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Go to mcmaster carr and order a 1/2 diameter rod, cut it to length 6".should weigh about 5.5 oz. While tungstun shothas twice the density of steel, tungsten shot has lots ofair voids that greatly dimish the difference. The other option is a solid tungsten rod. Then you would have 10.5 oz the most you can fit in that space. Better option is to drill the hole bigger.
 
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I'm thinking tungsten because it's 1.7 times the density of lead and I don't have tons of room under the butt to add weight.

Secondary reason is for the fact that tungston shot is a game changer in the .410 shotgun world.

The newest Turkey guns are .410s with tungston and they are outperforming what 12 gauge turkey guns were doing as far as pattern density and range a decade ago.

I'm picking up the .357/.410 version of this soon...
 
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This is what I was looking at, about 67 bucks a pound...

 
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Go to mcmaster carr and order a 1/2 diameter rod, cut it to length 6".should weigh about 5.5 oz. While tungstun shothas twice the density of steel, tungsten shot has lots ofair voids that greatly dimish the difference. The other option is a solid tungsten rod. Then you would have 10.5 oz the most you can fit in that space. Better option is to drill the hole bigger.

Yeah one thing is certain I won't be able to cut any rod once I get it. Don't have the tungsten carbide needed to do that.
 
If you use lead or steel rod, be sure to coat it with something to prevent oxidation. I saw a shotgun stock that cracked from lead shot in the stock that had oxidized and split it. I dunno if tungsten does that or not…or use a stainless rod.
 
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