southern mt. vs hawken rifles

[Black Jaque Janaviac]

I know Hawken rifles have bolts (not screws) that go through the wrist and thread into the trigger plate/guard assembly which strengthens the wrist area. How about southern rifles? I see that long tangs that extend way down the wrist are common but I don't see mention of bolts going through to the trigger plate.

 

[Ames]

The top one does. The one at the end of the lollypop is just a screw on any I handled.
It would, however, line up with the end of the trigger plate if you wanted to. I'd be nervous drilling a bolt through the wrist for a lollipop tangs little support. Not really gaining any strength.

 

[Pete G]

A lot of original SMR's used wood screws. Removes less wood through the wrist.

 

[Zonie]

The long barrel tang and long trigger plate I used on my Tennessee have long machine screws going thru them and the wood at both the front and at the rear.

This gives a great deal of extra reinforcement to the wood in the thin wrist.
Good thing that it does. The wood grain in this walnut stock is running parallel with the barrel (bad) rather than running in the direction of the wrist (good).

 

[Col. Batguano]

Zonie that looks like an accident waiting to happen with a. broken wrist. Did you put a bolt through it (the long way) or otherwise reinforce it?

 

[Zonie]

Zonie that looks like an accident waiting to happen with a. broken wrist. Did you put a bolt through it (the long way) or otherwise reinforce it?

No. I did not put a bolt or other reinforcing rod down thru the lengthwise direction of the wrist.

As I said, the long barrel tang on the top fitting snugly in it's mortise and the long trigger plate on the bottom fitting snugly in it's mortise has a screw connecting both the front area and the rear area of the steel.
That essentially makes a "wood sandwich" with steel acting as the bread. With both screws tight the 2 pieces of steel are compressing the wood perpendicular to the direction of the grain. It works the same as a vise with one jaw on the top of the wrist and the other jaw on the bottom of the wrist.
That should keep the wrist from cracking.

 

[david58]

I think caliber (recoil) matters. I am building a .40, and will use wood screws. The point of the rifle is a light charge squirrel shooter, not a shoulder cannon. I am pretty confident with the good, hard wood, nice heavy barrel, and little hole will all add up to being just fine with wood screws.

 

[Col. Batguano]

Certainly that is true for the firing sequence, both in the acceleration portion (firing) and the deceleration phase (your shoulder stopping it). I think the biggest risk however is accidentally bumping or dropping it. The weakest part of the gun is the wrist, and all those forces get concentrated there. The leverage forces trying to pry the wood apart through sheering force during the firing sequence are pretty small compared to those from bumping it when the gun is only supported at the top and bottom.

That's why grain direction through the wrist is so critical, as, when wood splits, it wants to split along the grain lines rather than across it. Small tight rings provide lesser sized cells (meaning less air in the wood) and stronger sheer resistance. If you have a lot of grain runout in the wrist, you have a rather short contact area between the rings that is effectively the wood's internal "glue line".

Wood species also makes a difference. Hard sugar maple has about a 25% greater sheer strength than red maple. There are numerous charts on that subject available in the public domain if you care to look for them, but you have to bear in mind that each individual piece of wood is slightly different.

In general, wood with a lot of curl in it is weaker than very straight grained wood. There is less "supporting wood" fore and aft of the force point to lend strength to the area of concentration.

Moisture content also makes a difference. Dry wood splits more easily than green wood, and there is a seasonality to wood moisture content.