I'm looking for advice on a new design that I have lodged a provisional patent on.
The action is quite unique. I have searched the patent literature extensively and haven't found anything similar. I won't provide great detail here- suffice to say it is something like a tilting bolt design without the bolt carrier.
Because the bolt does not require locking lugs it should be possible to produce a very cheap to manufacture bolt but I would like to make it even cheaper. I want to produce a gun that would be cost competitive with an SKS- hopefully in the $300 range (new), using AR-15 mags and specced for both military 5.56 and remington 223.
The aim is to produce a backup gun for the prepper movement who are currently unable to provide an AR-15 for their whole family/friends and tend to purchase WWII bolt actions or SKS and low grade AK-47 variants. I think a very low cost semi-auto compatible with AR-15 mags and ammo would be very sought after.
The idea is not to make a gun able to survive 50,000 rounds, but maybe 10,000- even if it takes a waiver to be signed by the purchaser. Most of these guns will just collect dust waiting for Armageddon and that's easier to accept at $300 a copy than $800-$1000 a copy.
My ideas to simplify the bolt and rifle cost are as follows:
In many bolt designs, a considerable amount of material is machined from the base of the bolt to allow it to pass over the mag lips. I think it would be easier to use a stamped steel "sled" shape piece that attaches to the bottom of the bolt. Probably two pins would be enough. The sled would also hold a channel for a full length ejector rod. The face of the bolt accepts the forces of firing as per normal. The sled just rides on the rails, the ejector fits between the mag lips, picks up the cartridge and feeds it into the bolt face recess as per normal.
By using a simple spring steel hook extractor at the top of the bolt and combined with the ejector rod sliding between the sled and the bottom of the bolt, the action would provide a simple vertical eject.
The only machining I see as totally necessary would be the recess on the bolt face for the cartridge- but there would be no need for a sophisticated extractor and spring.
The firing pin would be hammer fired because this can exploit the economies of scale of numerous hammer trigger groups on the market and keep the bolt simple.
I would like to know if this bolt would be better cast or milled in terms of cost. If cast, then the firing pin hole would need some kind of cast in recess to allow "gymnastic" fingers to insert a retaining spring on the firing pin and fit insert the assembled firing pin inside the bolt itself.
I'm also unsure if any cast bolt will need a minimal amount of machining anyway e.g. the firing pin hole may need to be drilled just to verify clearance. The pin holes for the sled attach to the bolt would need to be drilled as well as the hole for attaching the extractor spring. Pins may not be durable in these holes and hence they may need to be tapped for screws. Then there is machining the bolt face recess. If all this amount of machining is required anyway, would there really be any cost savings from just setting it up in a CNC mill and letting the whole thing be machined?
I'm aware that large production runs significantly reduce per unit costs and also that Ruger have great expertise in casting - after a significant investment in the technology.
Comments welcomed.
The action is quite unique. I have searched the patent literature extensively and haven't found anything similar. I won't provide great detail here- suffice to say it is something like a tilting bolt design without the bolt carrier.
Because the bolt does not require locking lugs it should be possible to produce a very cheap to manufacture bolt but I would like to make it even cheaper. I want to produce a gun that would be cost competitive with an SKS- hopefully in the $300 range (new), using AR-15 mags and specced for both military 5.56 and remington 223.
The aim is to produce a backup gun for the prepper movement who are currently unable to provide an AR-15 for their whole family/friends and tend to purchase WWII bolt actions or SKS and low grade AK-47 variants. I think a very low cost semi-auto compatible with AR-15 mags and ammo would be very sought after.
The idea is not to make a gun able to survive 50,000 rounds, but maybe 10,000- even if it takes a waiver to be signed by the purchaser. Most of these guns will just collect dust waiting for Armageddon and that's easier to accept at $300 a copy than $800-$1000 a copy.
My ideas to simplify the bolt and rifle cost are as follows:
In many bolt designs, a considerable amount of material is machined from the base of the bolt to allow it to pass over the mag lips. I think it would be easier to use a stamped steel "sled" shape piece that attaches to the bottom of the bolt. Probably two pins would be enough. The sled would also hold a channel for a full length ejector rod. The face of the bolt accepts the forces of firing as per normal. The sled just rides on the rails, the ejector fits between the mag lips, picks up the cartridge and feeds it into the bolt face recess as per normal.
By using a simple spring steel hook extractor at the top of the bolt and combined with the ejector rod sliding between the sled and the bottom of the bolt, the action would provide a simple vertical eject.
The only machining I see as totally necessary would be the recess on the bolt face for the cartridge- but there would be no need for a sophisticated extractor and spring.
The firing pin would be hammer fired because this can exploit the economies of scale of numerous hammer trigger groups on the market and keep the bolt simple.
I would like to know if this bolt would be better cast or milled in terms of cost. If cast, then the firing pin hole would need some kind of cast in recess to allow "gymnastic" fingers to insert a retaining spring on the firing pin and fit insert the assembled firing pin inside the bolt itself.
I'm also unsure if any cast bolt will need a minimal amount of machining anyway e.g. the firing pin hole may need to be drilled just to verify clearance. The pin holes for the sled attach to the bolt would need to be drilled as well as the hole for attaching the extractor spring. Pins may not be durable in these holes and hence they may need to be tapped for screws. Then there is machining the bolt face recess. If all this amount of machining is required anyway, would there really be any cost savings from just setting it up in a CNC mill and letting the whole thing be machined?
I'm aware that large production runs significantly reduce per unit costs and also that Ruger have great expertise in casting - after a significant investment in the technology.
Comments welcomed.