Comments refer to a 12 gauge 870. I will describe a malfunction that some experience. Bang, pump, click. This may not have been a short stroke. If not, this happened. Upon firing, recoil forced the shooters "pump hand" backwards a couple inches. This movement activated the forward shell latch to the position where it's role is retaining the next shell to be fed. Now, the shell in place to be fed into the action jumps forward past the forward shell latch. It is held in this position when the action is moved to the rear. Thus, there is not a shell to be fed. When the action is closed, we have an empty chamber. Click.
We talk about loading the 870 to a ready position by retracting the slide slightly and then pushing the shell past the forward shell latch. Then we retract the slide fully to the rear. Said shell continues to be held by the forward shell latch.This same thing occurs in the above example.
Two simple procedures will prevent this malfunction. One is consciously maintaining forward pressure on the fore end. Placing the pump hand on the rear portion of the slide helps maintain pressure. Visualize the angle formed by forearm and upper arm in this case.
The other procedure accomplishes this forward pressure without consciously pushing forward. Place the pump hand forefinger along the side the pump handle. This position will retard slide movement upon firing. Then we do not have this malfunction.
I have owned at least 30 870's and had the privilege of learning from factory trained armorers. There is no finer pump shotgun. However, Mossbergs don't have this defect. For this reason, I recommend the 500 series pumps.
I can demonstrate the above malfunction on demand. I can not demonstrate true short stroking. I do not deny that it exists, but if you tell me you short stroked your 12 gauge 870, I will doubt that.
In the above example, I said that the shell jumped forward upon firing. What happened was that recoil moved the gun backwards. The magazine tube moved past the shell. Increasing spring strength does not prevent this.
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