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FireHunter
.224 member


Reged: 11/07/06
Posts: 21
Loc: Southeast Oregon, USA
The importance of a third fastener?
      #63942 - 13/10/06 04:57 AM

I asked this question in another thread that got a bit sidetracked and never got any takers willing to offer up an opinion.

I am in the process of compiling all the pieces needed to build my first double rifle (not my first "rifle") and have yet to settle on an action. I have been lead to believe that a third fastener is absolutely necessary for these shotgun conversions yet I have seen more than one conversion that had no third fastener and the shooters are still alive to talk about it.

I am not debating the type of third fastener involved, just wether a third fastener is a necessity or a "nice-ity". Say, for a 450 3 1/4" NE or larger cartridge.

Thoughts?

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Just because you can, doesn't mean you should!


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FireHunter
.224 member


Reged: 11/07/06
Posts: 21
Loc: Southeast Oregon, USA
Re: The importance of a third fastener? [Re: FireHunter]
      #64035 - 15/10/06 01:33 AM

Hmmmmmm, guess it's not that important. Thanks for all the input.

--------------------
Just because you can, doesn't mean you should!


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400NitroExpress
.400 member


Reged: 26/11/03
Posts: 1154
Loc: Lone Star State
Re: The importance of a third fastener? [Re: FireHunter]
      #64054 - 15/10/06 10:50 AM

I can only speak to this issue from experience with purpose built double rifles.

While many "best" shotguns have no rib extension, I believe that double rifles should and I try to avoid those that don't. If it has a third fastener of the screw-grip type, great. If not, I prefer that it have none at all as, from observation over the years, I don't think any of the others work.

A friend of mine has a British .450 No. 2 NE that has a dolls head, but no third fastener. It was 90+ years old when he got it, and he's put 3000 rounds through it since then, and it's still tight on face. Likewise one of mine has only a dolls head with no third fastener, was old when I got it, and I've put quite a few rounds through it since then, and it's still tight on face. I would guess that I've seen as many DRs with third fasteners off face as I have without, except for the screw-grips.

Perhaps since the converters are using shotgun actions, they think a third fastener will make up the difference. I think they're kidding themselves. Either the action is strong enough or it isn't. At the range, when folks shoot shotguns converted to DRs, I go hide behing a nice cast-iron engine block.

The need, or not, for a third fastener has nothing to do with bore size.
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"Serious rifles have two barrels, everything else just burns gunpowder."


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500grains
.416 member


Reged: 16/02/04
Posts: 4732
Loc: Salt Lake City, Utah USA
Re: The importance of a third fastener? [Re: 400NitroExpress]
      #64058 - 15/10/06 01:53 PM

I have heard many people question whether the Greener cross bolt actually does anything. Personally I have no opinion, but it is fun to watch it work.

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DUGABOY1
.400 member


Reged: 02/02/03
Posts: 1340
Loc: TEXAS USA
Re: The importance of a third fastener? [Re: 400NitroExpress]
      #64079 - 16/10/06 09:14 AM

In reply to:

A friend of mine has a British .450 No. 2 NE that has a dolls head, but no third fastener. It was 90+ years old when he got it, and he's put 3000 rounds through it since then, and it's still tight on face. Likewise one of mine has only a dolls head with no third fastener, was old when I got it, and I've put quite a few rounds through it since then, and it's still tight on face. I would guess that I've seen as many DRs with third fasteners off face as I have without, except for the screw-grips.





This is only a matter of semantics, I'm sure, but I've always considered a dolls head, and hidden rib extention, to be a "THIRD FASTENER" with the two under bites, being numbers one, and two! The screwgrip,and the Greener corss bolt, to me, being the fourth fastener!

The screw grip is most usually coupled with a doll's head, haveing a bite in the nose of the doll's head, for an angled top lever extention to engage. The angle pulling the doll's head down as the lever goes back to center after closeing the rifle. If one examines the greener cross bolt closely, you will find the cross bolt doesn't engage the rib extention from a 90 deg angle to the extention, but engages the hole at a shallow angle, working the same way as the screw grip, by the silghtly tapered pin pulling the barrels down as it slides home.

It is true, however, that not all greener cross bolting is properly done, as is the case with cheaply made screwgrips. An example of this is an old MIssissippi Arms 12 ga I own, is equiped with a very sloppy screw grip, that barely engages the extention at all.

As far as a double rifle needing a third, and/or fourth fastener, I believe the more lock-up one has the better. That, however, is in no way saying, a double rifle without a fastener of any kind other than the under bites, is automaticlly a weak rifle. That depends on many things, not the least of which is the chambering!

I agree with Mark, in that most shotgun conversions can benifite from a third, and fourth fastener. Haveing said all the above, most "off face" condition found in a double rifle can usually be traced back to poor care, more than lack of lock-up. The biggest offender is the guy who never lubes the hook/ pin mateing surfaces, or lets them rust, dirrectly causeing the looseness, more than the type of fastening in the rifle, or pressure.

Just my 0.02 cents!

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..........Mac >>>===(x)===>
DUGABOY1, and MacD37 founding member of DRSS www.doublerifleshooterssociety.com
"If I die today, I have had a life well spent, for I've been to see the Elephant, and smelled the smoke of Africa!"


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WildCattle
.275 member


Reged: 22/03/06
Posts: 95
Loc: Northern California
Re: The importance of a third fastener? [Re: 400NitroExpress]
      #64080 - 16/10/06 09:32 AM

My belief is that a long bar (i.e. the distance between the hinge pin to the breech) is more important that the 3rd grip. It is hard to find a shotgun action with a long bar, as it is heavier than a short one, and not really necessary on a shotgun.
It is no coincidence that most Webley rifle were built on their long bar action.
All my shotguns have a bar shorter than 2", while all my double rifles have a bar longer than 2". Fluke? I think not...
IMHO, a long bar gives more leverage to the bolts as well as a reduced "deflection" angle (the angle between the bore center line and the line from the firing pin to the hinge pin. Both of these will reduce strain to the Purdey bolt and/or the 3rd grip, whatever it is.
The idea of the 3rd grip is to reattach the barrel to the top of the action, which goes in the right direction as well, assuming that it is well done. I think that the problem with the 3rd grip is that it is mighty hard to have an effective one, as the adjustments involved are difficult.
A long bar also reduces the sideways strain due to the excentricity of the left and right barrels. This aspect is mitigated by a doll's head and/or sideclips which help reduce lateral motions. The reason is that a longer bar usually implies a longer lump, which helps in absorbing the lateral torque.

It must be said that a rifle built on a short bar action or without a 3rd bite will probably survive. The question is: how long?
The more margin to start with, the better off we are...

To sum it up, I think that:
- a longer bar is better
- a bar with minimum internal cutouts is better (such as back-action sidelock). Side bolsters also help.
- the less slop to begin with, the better
- a 3rd grip is fine but not absolutely necessary
- ditto for sideclips

Long bar shotgun actions are found on Greener Empire (*not Facile princeps*), some German guns, and some older guns as well as some of the cheaper guns.

Shotguns and rifles were built on different actions for good reasons, hence finding a suitable shotgun action to build a rifle is not easy!

WC


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You know you have reached perfection of design not when you have nothing more to add, but when you have nothing left to take away.
Antoine de Saint-Exupéry


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FireHunter
.224 member


Reged: 11/07/06
Posts: 21
Loc: Southeast Oregon, USA
Re: The importance of a third fastener? [Re: WildCattle]
      #64085 - 16/10/06 12:13 PM

Excellent! This information is exactly what I have been wanting to hear. The comment on finding a suitable action being somewhat difficult is exactly what I am up against right now. I was interested to see if my standards were a bit high but it sounds like I should hold out for exactly what I was looking for.

The info about the "bar" being longer on rifles (more than 2 inches) was new to me. It may sound remedial to some, but it helped my comprehension a great deal. Thanks again.



--------------------
Just because you can, doesn't mean you should!


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DoubleD
.400 member


Reged: 23/11/03
Posts: 2416
Loc: Retired in Oklahoma
Re: The importance of a third fastener? [Re: FireHunter]
      #64088 - 16/10/06 12:49 PM

Could it be/is it that the third fastener serves the same purpose as the third lug on a Mauser bolt. It's there to catch things if the others fail?

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DD, Ret.


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DUGABOY1
.400 member


Reged: 02/02/03
Posts: 1340
Loc: TEXAS USA
Re: The importance of a third fastener? [Re: DoubleD]
      #64274 - 19/10/06 07:35 AM

In reply to:

Could it be/is it that the third fastener serves the same purpose as the third lug on a Mauser bolt. It's there to catch things if the others fail?




Absolutely, It is a back-up safety catch, but properly fitted a dolls head is also an effective third fastener, as well!

--------------------
..........Mac >>>===(x)===>
DUGABOY1, and MacD37 founding member of DRSS www.doublerifleshooterssociety.com
"If I die today, I have had a life well spent, for I've been to see the Elephant, and smelled the smoke of Africa!"


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