No Recoil Lug - What say ye?

[Pdvdh]

Paul, Stu, there is no place for a recoil lug to be fitted in the stock. It's the tang that is taking it.

I will call Beretta TS tomorrow and ask them what is going on with no recoil lug.

Mark

Can't wait to learn what Beretta's explanation is. There must be a hose-nose on staff somewhere in the Sako research and development section. I've never seen a high powered rifle that used the tang of the receiver as the primary recoil lug. I don't understand why a rifle designer would ever want to place the entire action until the full load of recoil. Doesn't surprise me too much that the rifle won't drive tacks as is.

I liked the idea of tig welding a recoil lug into the slot in the receiver on my T3s. The gunsmith in the other thread said he was certain that could be done safely by an experienced tig welder (which I am not). That's what I was tempted to do with mine - take it to an experienced tig welder - but I never got that far. Then a corresponding slot could be hogged out of your stock and the barrelled action could be bedded the same as most other bolt action rifles. I would relieve the tang from contact with the stock at that point. Let the "real" recoil lug handle recoil and remove the stress & strain from the receiver.

I even looked into aftermarket stocks for the Tikka T3s because my rifles shoot so well. The closest I got to a lead on stocks was that Robertson (a Canadian stock manufacturer) made stocks for the Tikka T3s. I looked at their web site and didn't see the Tikka T3s listed as a standard production stock. But I never did call Robertson to get a confirmation - yea or nea.

 

[NesikaChad]

I don't understand why a rifle designer would ever want to place the entire action until the full load of recoil. Doesn't surprise me too much that the rifle won't drive tacks as is.

Let me start off by saying I'm not picking on anyone. The above quote follows standard bolt gun doctrine pretty much to the letter.

We'll just call this a "high minded" discussion.

Take a piece of steel and compare it to wood, fiberglass, or aluminum. Using nothing more than the good common sense we are born with it's not hard to pick the one that is going to be strongest and most resilient to impact and compression loading.

The average rifle stock is just under 2 inches in width where the receiver sits. A typical magazine box is around an inch in width. This means that when a repeating rifle with a floor metal is assembled and in service it has two sides that are roughly just under half an inch in thickness. As we go up in caliber size, this dimension will decrease some due to the bigger mag box.

Traditional bolt guns have the recoil lug up front. This means that the two half inch slabs are seeing the brunt of the impact, torsional, and tensile loading delivered by the barreled action during the firing event and then transmitting that energy through the grip, the butt, and eventually to your shoulder in the form of recoil. On big calibers it's a common practice to cross pin a stock. This is done to mitigate the stock splitting in two halves behind the recoil lug and its a common practice on dangerous game rifles chambered in a boomer class calibers.

The reason is the sides of the stock bow out during recoil. Place your hands against one another as if your in prayer, now bend your fingers while keeping the palms and fingertips in contact. This is exactly what a stock does during recoil.

Using that thought process what is so terrible about the action bypassing all that drama and using the tang instead?

I own a rifle done just this way and it's the hardest hitting gun I own. It's in a lighter caliber (22-250) so it'd be really speculative for me to say that bigger cartridges don't change the rules a bit, but it is at least encouraging. It too is a flat bottom action.

I think that so long as the tang area is big enough to not break the tang portion of the grip off the gun a rifle built this way will work just fine and may even be a bit better. It's a theory at this point so don't fillet me too bad.

Comments welcomed.

Chad

 

[Pdvdh]

Chad,

Glad you've joined this thread. Good to hear from another of the smiths that share on this forum. I've never seen a production line high-powered big game hunting rifle designed this way. Curious as to whether or not you have since you've seen a few bolt action designs over the years.

It didn't sound to me as if the tang of MontanaRifleman's Sako was even designed to the size of standard recoil lugs. Mark stated "The only place I can see where recoil is being transferred to the stock is in the tang area of the receiver which is somewhat thickened - about 3/16" and recessed into the plastic stock. That's it."

Steel is strong, but placing the recoil lug at the base of the tang on a repeating rifle really doesn't make good sense to me because the action isn't symetrically strong on both sides. The ejection port side, combined with the magazine cutout underneath repeater bolt actions means that that side of the receiver is missing a lot of steel present on the other side. There's just a small strip of steel on some of my repeaters versus a solid slab of steel on the opposing side. And the tang is located such that the major portion of the compressive recoil force would be directed along the bottom of the action, right along that poorly supported section of the action. If the actions were symetrical (meaning one side was the spit'in image of the other) and sufficiently reinforced to prevent flexing and torsion, then the action would be better suited to transfer the recoil force of heavy kickers - my opinion from an engineering background.

I know actions are beefed up on high powered target rifles. One way to do this is eliminating the cutout for the magazine boxes and go single shot bolt action. Now the action is only skeletonized for the ejection port.

I think the bedding on light kicking rifles isn't so critical since they don't impart anywhere near the recoil forces of the 30 caliber magnums. I've got some .22's without any recoil lug.

I'm looking forward to hearing Beretta's explanation. No offense intended toward anyone but I am questioning the guy that left the recoil lug out of the design of the Sako. I still think they boned it on the design and production of this bolt action. A 3/16" protrusion off the tang isn't a legitimate recoil lug - it's an oversight.

PS: Chad; in your opinion is it possible to tig weld a recoil lug into the slot present for a recoil lug on the bottom of this Sako action without detrimental effects from the heat stresses of welding causing problems with the strength of this action? Thanks.

 

[MontanaRifleman]

Here's the latest. The guy at Beretta said there was an aluminum block in the stock and it should be milled to fit into the slot. I told him it was plastic and flat and he said, "are you sure?" On more close and careful examination, I found that it was alumiinum painted to same black plstic color of the stock by scratching at it with a screw driver. The block is a piece of angle as someelse here said. However, there is no milled area to fit into the slot of the receiver. It is flat. I sent pics to the guy at Beretta this afternoon and will talk with him tomorrow. I'm guessing they will send me the correct part to instal.

Pics coming.

Mark

 

[Pdvdh]

I sent pics to the guy at Beretta this afternoon and will talk with him tomorrow. I'm guessing they will send me the correct part to instal.

Pics coming.

Mark

Pics will be interesting. So there really wasn't any functional recoil lug. Wow. Sounds like it was just a cluster and not by intent or design. Maybe it'll be a shooter with a functional recoil lug. I'm kinda surprised there isn't some damage to the stock or action screws from recoil. Better look around in there and check over the action screws to see if they've bent or deformed in any way.

How much load development effort have you put into this gun? Is this a rifle that you've sent back to the factory for inspection? Or was that a different rifle?

 

[MontanaRifleman]

The "recoil lug" in the stock. Completely flat except for the recess milled out fo the action screw lug. It's a snug fit, but it's basically floating.

The tang... where all the recoil was being absorbed. There is a lower recessed area for the boss of the action screw.

 

[MontanaRifleman]

The "recoil lug".

The receiver... you can see the slot on the flat under side.

A couple of views o f the tang.

 

[MontanaRifleman]

Pics will be interesting. So there really wasn't any functional recoil lug. Wow. Sounds like it was just a cluster and not by intent or design. Maybe it'll be a shooter with a functional recoil lug. I'm kinda surprised there isn't some damage to the stock or action screws from recoil. Better look around in there and check over the action screws to see if they've bent or deformed in any way.

How much load development effort have you put into this gun? Is this a rifle that you've sent back to the factory for inspection? Or was that a different rifle?

I've got pics of the receiver too, but I need to get going to help my son out. BBL

 

[MontanaRifleman]

Paul, to answer your questions, this rifle has been back to the factory twice. Each time, they said they inspected it, cleaned it and fired and sent it back with a Oehler computer generated target (no bullet holes) and said it shot to spec, good to go. They basically said my problem was fouling - said my bore was fouled when they cleaned which it wasn't.

Read this thread...

http://www.longrangehunting.com/forums/f22/beretta-customer-service-47493/

I'll be updating it.

And yes, I have done quite a bit of load development for this rifle. I tried 2 powders and 4 types bullets, including some of the HAT's I got from you. I got very sporadic "groups" and I suspect that this recoil lug issue is behind it. I shot 3 boxes of factory ammo through it trying to see what it liked as well as about 200-250 handloads (including break-in) Then there is four trips to the gun dealer that is 60 miles away to drop off and pick up the rifle.

I hope this will fix the problem.

 

[MontanaRifleman]

Now, if I decide to pillar and full receiver bed this rifle, how do I go about it? The lug floats in the stock and the bottom of the receiver floats on the lug. The action screw boss does not appear to make contact with the lug. There is realy nothing to keep the receiver from shifting side to side.

Oh yeah, there doesn't appear to be any damage to the action screws or stock. It may be plastic, but it's tough plastic.

 

[Pdvdh]

Post a picture of the bottom of the action and maybe our gunsmiths will sound in. I don't think there's anything that can be done with the recoil lug shown in the photos. It does nothing to secure the action to the stock against the backwords force of recoil.

This stock is much different than my Tikka T3s. I'm eager to see a photo of the bottom of your Sako action, as the action sounds to be built just like my Tikka T3s with the slot to accept the recoil lug. Which in your case is not being utilized.

Post a photo of your action and see what Chad or the other smiths have to say.

Oh yeah, if the Beretta folks disassembled your gun twice now, then they either forgot to install the recoil lug, or they never noticed the recoil lug was missing. There's got to be something missing that is supposed to engage the slot cut into the bottom of the receiver.

Either way, it looks like a thumbs down for Beretta/Sako on their rifle inspection and return process. They need to send you a functional recoil lug. I don't know if I'd send it to them again... they might forget to install the barrelled action in the stock before returning it...

 

[jmden]

MR,

Wow. I hope you can get to the bottom of this and have an accurate rifle quickly. You have really been through the ringer on this one. Too bad.

Very interesting design on that rifle

Keep us posted,

Jon

 

[MontanaRifleman]

I edited the pictures of the receiver into the post with the pics of the lug. And yeah, they sure overlooked the missing lug

 

[Pdvdh]

Ahh. Now I see the pics of the receiver.

It looks to me like the boss around the front action screw is the recoil lug, provided that the boss extends down into the recess shown in the top side of the lug. The barrelled action would drive the boss against the recess in the recoil lug, and then the recoil lug would drive back against the slot in the stock, located forward of the front action screw. No?

That's what I conclude from your photos. The front action screw boss contacts the back of the milled out section in the lug, and then the lug transfers that backward force into the stock where the angled end of the lug is engaged down and against the back of the recess in the stock. What do you think?

My Tikka T3 actions look like the bottom of your Sako action except that they have no boss cast into action surrounding the threaded front action screw hole. Their recoil lug consists of a plate of metal engaged into the recess in the action, and a location matching recess in the stock. The lug is fastened to neither the action or the stock, but it's trapped into place with the action is screwed down to the stock.

I think I better understand J E Custom's post on your Sako action now that I've seen the photos.