barnbwt
member
- Joined
- Aug 14, 2011
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- 7,340
A few more thoughts on this, and why recoil operated designs are not necessarily the best 'hot rod' platforms
-Necked rounds generate a lot more thrust on the barrel/slide lockup, since there is pressure-bearing area on the barrel-side of the chamber in addition to the breech
-Peak lug thrust is seldom the limiting factor in handguns, for sure in 1911/Tok/Hi Power style multi-lug platforms (see: 460 Rowland)
-Recoil is what operates recoil-operated guns, not pressure
--Therefore increasing recoil by itself is akin to 'overgassing' a gas operated gun; recipe for reduced life or breaking stuff
--Like an overgassed gun, an over-accelerated slide runs much rougher, breaking things
--Like a severely overgassed gun, an over-accelerated slide can result in timing issues, to the point of case head failure!
--Like a gas-operated gun, recoil actions are tuned to work within a fairly narrow band of operating energy (recoil/momentum in this case), and cannot be expected to operate reliably/safely very far outside this range without redesign
--Unlike a gas-operated gun, there aren't very good methods to throttle the energy delivered to the operating system (muzzle brake is it)
-Pressure/temperature are not high enough for a long enough duration to damage overbore barrels like rifles can, there is simply not enough powder to 'sandblast' the throat all that much, nor enough velocity. Cold hammer-forged 357 MR73 revolvers can run many tens of thousands of rounds (if not hundreds by now) of full power mags without detectable wear.
-Most important; no one marketing a newer, more powerful chambering ever bothers to modify or design a new platform whose design variables are optimized for it. It is simply too expensive. So the best you get is 'long slides' which use weight to slow things down, or muzzle brakes to divert some of the recoil energy against escaping gas. Otherwise, pretty much all of them function by pressing the operating energy envelope just a little bit further than ever intended by the original designers, who optimized the weight/timing/etc for a lower power cartridge.
Unlike a gas-gun which can easily shield the operating system from the increase in cartridge power by using a smaller gas port or a cutoff mechanism, a recoil operated gun has to soak up all the recoil energy there is available. Puts a hard ceiling on how much momentum your cartridge can deliver at the end of the day, and the closer you get to it, the more you abuse the machine.
Proper design is always a good thing, and can solve pretty much all problems like these that are caused by playing with a few variables...but it's also too expensive for folks just funnin' around with new cartridge ideas
(FWIW, I believe that rapid prototyping and CNC will eventually make this type of iterative design-by-empirical-experimentation viable, and ultimately lead to new/better optimums than we have reached to date)
TCB
-Necked rounds generate a lot more thrust on the barrel/slide lockup, since there is pressure-bearing area on the barrel-side of the chamber in addition to the breech
-Peak lug thrust is seldom the limiting factor in handguns, for sure in 1911/Tok/Hi Power style multi-lug platforms (see: 460 Rowland)
-Recoil is what operates recoil-operated guns, not pressure
--Therefore increasing recoil by itself is akin to 'overgassing' a gas operated gun; recipe for reduced life or breaking stuff
--Like an overgassed gun, an over-accelerated slide runs much rougher, breaking things
--Like a severely overgassed gun, an over-accelerated slide can result in timing issues, to the point of case head failure!
--Like a gas-operated gun, recoil actions are tuned to work within a fairly narrow band of operating energy (recoil/momentum in this case), and cannot be expected to operate reliably/safely very far outside this range without redesign
--Unlike a gas-operated gun, there aren't very good methods to throttle the energy delivered to the operating system (muzzle brake is it)
-Pressure/temperature are not high enough for a long enough duration to damage overbore barrels like rifles can, there is simply not enough powder to 'sandblast' the throat all that much, nor enough velocity. Cold hammer-forged 357 MR73 revolvers can run many tens of thousands of rounds (if not hundreds by now) of full power mags without detectable wear.
-Most important; no one marketing a newer, more powerful chambering ever bothers to modify or design a new platform whose design variables are optimized for it. It is simply too expensive. So the best you get is 'long slides' which use weight to slow things down, or muzzle brakes to divert some of the recoil energy against escaping gas. Otherwise, pretty much all of them function by pressing the operating energy envelope just a little bit further than ever intended by the original designers, who optimized the weight/timing/etc for a lower power cartridge.
Unlike a gas-gun which can easily shield the operating system from the increase in cartridge power by using a smaller gas port or a cutoff mechanism, a recoil operated gun has to soak up all the recoil energy there is available. Puts a hard ceiling on how much momentum your cartridge can deliver at the end of the day, and the closer you get to it, the more you abuse the machine.
Proper design is always a good thing, and can solve pretty much all problems like these that are caused by playing with a few variables...but it's also too expensive for folks just funnin' around with new cartridge ideas
(FWIW, I believe that rapid prototyping and CNC will eventually make this type of iterative design-by-empirical-experimentation viable, and ultimately lead to new/better optimums than we have reached to date)TCB
