[backbencher]

Rather impressive - it runs:

The Overmass Project: World’s heaviest 9mm blowback action? (with videos)

 

[moona11]

Really

 

[ajole]

So, now we know…..

I thought Hi Point already established that heavy slides will run 9 mm.🤣

 

[LTP1]

He needs a chronograph and a calculator and most of his experiments wouldn't be a surprise to him.

 

[RACHGIER]

He needs a chronograph and a calculator and most of his experiments wouldn't be a surprise to him.

How DARE you expect someone to properly execute the scientific method!!!

 

[Blowback9Guy]

So, now we know…..

I thought Hi Point already established that heavy slides will run 9 mm.🤣

How heavy? 2.3+ pounds heavy? That's how much it could cycle with a custom tiny barrel in the experiment. Is that how heavy Hi Point slides are? I don't have one to weigh. It looks like you have a few, could you please weigh them for me and report the weights, or are they listed somewhere?

He needs a chronograph and a calculator and most of his experiments wouldn't be a surprise to him.

I'm the guy who did the experiment and reported the results.

I don't know if you're just talking smack or are serious. If serious, please describe how could we determine the maximum blowback mass a system and cartridge could cycle by using a chronograph and a calulator. I'm always willing to learn and I'd love to see an example of the math. The only surprise to me was that my particular 147's didn't cycle the mass the 115's could. That's hardly "most" of my experiments. Sure a chrono might have told me that, but I don't have a chrono and it's not a priority with my small budget. Just a one man show here and I wouldn't use it enough to justfy the cost. If you can spare one, I'll give you a shipping address.

How DARE you expect someone to properly execute the scientific method!!!

I do not think "scientific method" means what you think it means. I used to teach science, so I'm a little familiar with it. It's a 6-step methodolgy; a process of inquiry and investigation. You don't need lab certified instruments, or a laboratory, or even math to follow the process properly. It goes like this:

Observation: I can run a 5.5" 9mm AR with 27oz. More than what some people say it should be able to handle.
Research: I can't find where anyone has actually physically tested to see how much mass a 9mm AR can cycle.
Hypothesis: It can cycle a lot more mass than most people think it can. Let's see how much with a very short barrel.
Test with experiment: Live fire with 37.5oz (2.3lbs.) of mass, the max I could stuff in the system, 2.5" barrel.
Analyze data: 2.5" barrel will cycle all of it with 115's. 2.5" barrel barely won't cycle with 147's.
Report conclusions: Any commonly available barrel (>3") should cycle any amount of mass you can stuff into a 9mm AR with a carbine buffer tube and commonly available parts and ammo.

Was the experiment perfect? No. No experiment is perfect. Was it good enough? I certainly think so. Is it repeatable and potentially falsifiable? Absolutely.