Action Types Pro's and Cons

S

Seeker

New member
In another thread a fella commented that he preferred a bolt action. I reason that a bolt action has greater muzzle velocity than a semi-auto, as some of the gas pressure is used to cycle the semi-auto. Am I correct here?

If I am correct in my above statement how do pump actions compare to bolt actions (and semi-autos)? I don't have any bolt guns but I do have a nice set of pump action rifles (30.06, .35, and .22).

Don't see pump actions discussed much and thought this topic might be as much fun as the merits of the M-1 Carbine.
 
The main advantage of a bolt gun is weight; it's the simplist repeating action around, so the fewest parts and least weight. It can also be very stong and is adaptable to many calibers.

Velocity wise, any manually cycling action (pump, single shot, lever) is equal in velocity and can be nearly as light.

Semiautos lose a little velocity, but not that much. Probably about the same as only an inch or two of barrel length. Some semiautos are capable of excellent accuracy, at least as good as a standard profile hunting rifle, though not the highest levels of accuracy due to the need for well crimped, durable ammunition and slightly looser chamber tolerances. Some rifle's gas systems also works against consistent velocity and accuracy as the gas tubes clog and change back pressure. Also, autos are heavier and often require a heavier trigger pull for safety.

That being said, don't let anyone tell you that only bolt guns can be truly accurate. Shoot the following and you'll see that relatively great accuracy can come in many forms:

Marlin 30/30 lever action
Browning BAR and BLR auto and pump
Savage 99 lever
HK91 auto
M1A
AR15 heavy barrel

All of those will shoot 1moa or sometimes better. The typical $400 Remington or Win. bolt gun has trouble holding below 2 moa consistently. Velocity really comes down to barrel length. If your friend wanted the highest velocity for a given overall length of rifle, he should use a single shot.
 
Dittos on Handy.

The gas port on a Garand, for instance, is way on out by the muzzle. The gas pressure at the little port is already down to around 2,000 psi. Very little pressure is lost in the bleed-off. Handy probably made a conservative guesstimate as to any velocity loss...

Even for port locations well back, as in the GI Carbine, the loss of gas pressure is very, very small.

A pump-gun locks into battery and is not cycled until after the pressure is back to zero--you just can't move that fast! Any rotating-bolt pump-gun is as strong as a bolt action, allowing the use of full-power ammo. So, velocity only varies as the length of the barrel.

FWIW, Art
 
The advantage of the pump gun is speed, since one can be fired much faster than a bolt action (yes, Lee-Enfield fans, I know about some trick shooters, but I am talking about normal folks).

The pump gun, whether rifle or shotgun, is worked while in recoil, and without taking the firing hand off the grip and the trigger (you can't do that even with a SMLE). In areas where semi-auto hunting rifles are banned (e.g., Pennsylvania), pump rifles are very popular for that reason.

Jim
 
You must log in or register to reply here.
Back
Top