whats wrong with my shotgun?

Try hand cycling with one in the chamber and one in the mag. When you eject the shell the cartridge carrier should be holding the next shell in an upright locked position. If the shell is still in the mag it could be a weak mag spring. If the carrier is not in the up position it could be a broken actuator spring.

I had an 1100 lock back on me and it was a cracked handguard.

I had same problem and mechanically looked like it should work. I was using Unique reloads and every so often it wouldn't cycle. I changed to Promo reloads and it wouldn't cycle at all and then I tried 800X reloads and it worked perfectley through 4 boxes of

shells. Guess what Unique is a moderately fast powder. Promo is a fast powder but 800 X is a moderately slow powder giving the mechanism more time to operate. I haven't tried Herco reloads but they should be they equivalent of the 800x. Just me experience.

The gas system probably needs a thorough cleaning.

edit: Not very familiar with this shotgun, but if it was a Remington 1100 I'd start thinking about the O-ring. Hint, hint...

Its been a while since I looked at a shotgun, but if its a gas operated gun the o-ring on the piston may be worn.

Thats common on auto's. Its kinds like break pads on a car- they eventually wear out. It should be cheap to replace.

lots of semis won't cycle low brass shells......need to adjust or replace the gas tube o-ring and hopefully that fixes it...

so if it cycles buck/slug then ur next step is to try some high-brass birdshot....

if it still won't cycle u can have a gunsmith adjust the gas porting holes......might be too big or too small or not enough of them....

the rem 1100 need 2 to cycle low brass reliably....

Actually the gas system on a Higgins Model 60 shotgun like yours IS ADJUSTABLE! there were two systems, the early one used a large spring, the later one used a series of wavy washers. They both control how much gas is allowed to bypass (escape from) the gas system. There is a large nut that adjusts the tightness - tighter = less gas escapes. The standard setting is 15 rotations on the nut - start there and adjust accordingly.

I have the same Model.* Chances are you have not reassembled it correctly, but you think that you have.* If it worked before you took it apart before cleaning it: it should work after you cleaned it and put it back together.*

check the following:

stock spring

O ring

gas ports

staked in piece holding rounds in magazine tube

tuning fork

If not any of these take it to a gunsmith

There could be a lot of residue from when the previous owner used it.

clean it and clean it agin ok,,,,,,