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Old vs New 500 20ga Internal Parts Interchange Help.

andy38340

.22LR
Looking to see if any one knows how much of the internals of the old models will swap into a new model and vice versa.

I understand about the single bar and double bar action tubes having to match the receiver. Let's say I had an newer bolt and bolt slide. Would it work with an older single bar receiver and action tube?

I just acquired 3 older style 20ga receivers that will need internals. Just trying to get an idea of what will and wont fit.

Thanks for any insight.
 
For the 500 series internals should interchange. As long as the gauge is the same.
If I am wrong there are plenty of experts on the forum that will correct me if I miss spoke.
 
LTB is right.

The only parts you'll need to look at are the old style bolts/firing pins. Old bolts require old style firing pins and vice versa. Go new. No probs. Bolt carrier, same. Interchanges. The old style mag tubes with the spiral standoff bushings will require old style slide action tubes and castle nuts. Go new, again, and avoid all the probs. Some old stocks were made with white spacers at the wrist and won't quite sock down tight without some minor work. You probably wont ever see any. Other than all that, your guns will work just like modern ones. Easy to upgrade a Mossy with new parts!
 
Is the barrel notched for an extractor on both sides to accommodate the bolt on both the old and new guns?
 
I don't know anything about single action bar guns. In the twin action bar guns the guts didn't change much and are generally interchangeable.

Old bolts have a specific locking block (carrier), and the new bolts have their own locking block. Different style bolts and blocks do not match up, but the entire assembly is completely interchangeable.

There are two styles of interrupter that are totally interchangeable.

New triggers won't fit old guns. Either enlarge the cuts on the receiver or get an aluminum trigger.
 
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