My first guess would be that it needs a real good cleaning, this is a gas operated and not a recoil action. They haven't made them in about 50 years there might be a bit of junk in there ;) Remember this is also Remington's first gas operated shotgun it and there have been a lot of improvements it won't be as forgiving as modern versions.
Close, but no cigar. Your Montgomery Ward's shotgun Model 6OOERI is the Remington model SPT 58. You can get the firing pin from gunpartscorp.com for $12 plus hipping. It is part number 100170D.
The Remington Society of America has a services/parts link too but e-gunparts.com is a good place to start.
If it's a 16 gauge shotgun, the shell length is 2 3/4 inches.
Odds are it isn't a Remington at all, but rather an Ithaca Model 37. To my knowledge, it was the only bottom-eject pump shotgun ever made. As for value; any gun (or anything else for that matter) is worth whatever another is willing to pay for it.
yes the butt stocks are the same the barrels are also the same the only difference ison the 58 you need to have two holes drilled into the barrel. the holes allow the pressure to eject the shells.
No such model in the Remington line.
Angle Eject
No such model in the Winchester line. Remington has the 1100
Action size.
No such model number listed on Remington's web site.
No such model number in the Remington line
it is 56 Remington rifle model