Also known as.a bumpslide, I bought an ssar15 bumpslide for my ar-15 and was wondering if its aloud at public gun ranges

That is for the rangemaster to decide. A bumpslide is still considered semi automatic. But it boarders on class 3 weapon. The obvious question is that of control. Most "controlled" ranges won't allow rapid fire without a malfunction happening. Most public uncontrolled ranges may allow it as no rangemaster is on site and so long as you have full control of the weapon. So long as others around you don't mind you using it then it would be OK. But if anyone complains then its your obligation to stop. Also if the range is near a ranger station then ask them first about rate of fire.

Keep us posted on how you like the system.

The ranges I go to, would not allow, but again, "public" means private owned and each owner will have their own rules.

Call the range and ask. Many that allow full auto fire frown on bump fire and trigger manipulation devises legal or not call and ask. With the current administration this type of stuff is not cool. Even if it is "LEGAL" you may still need a lawyer to prove it. Many ranges will rent full auto weapons for use in their facilities all in all the best bet you can try different weapons and you are not burning up your barrel.