Algodoo

that's not a problem if your barrel is reasonably long and your bullet has a circle that only collides with the gas block-thingy. You make the bullet light and the circle that collides with the gas system heavy, so after it gets killed the bulet can get a lot of velocity

Also Meerkoos did his true blowback system so that the bullet was out of the barrel before the shell got dechambered. What you're doing is act the gas system when the bullet is 70 meters away from the barrel. The gas system should start acting even before the bullet is out of the barrel given that the gas tubes are always fixed close to the tip of the barrel (but there should be no pressure after the bolt lock is disengaged)

I think the biggest problem with guns made in Algodoo is the fact that most scenes (including this one) are not drawn to scale. For example, I measured one of the bullets, and it weighs 3.9 Kg (about 8.5 pounds, for you people in the U.S.)! And it is 60 cm (over 2 inches)long by 25 cm (1 inch) diameter! A bullet that large and that heavy cannot possibly behave like a rifle or pistol bullet in real life. I did not measure other parts of the guns in this scene, but I'm sure that they are also way out of what is considered a normal range for real life guns. Because of that, Algodoo physics cannot possibly behave as they would in real life. And, on top of that, a true gas-operated mechanism cannot be duplicated in Algodoo, and so people try to guess at how gasses would behave by making mechanical devices with levers and springs, which cannot come even close to real gas under pressure. Therefore, people can only do a rough approximation of a real gun, but in most cases, the physics are way off the charts.

Just my humble opinion....

@Xray
I can only agree on this. But another problem is that you can not really make a .22 diameter bullet in algodoo just because grid would not allow you and the physics don't work as they expected in this scale so you must compensate in size or in density. And at this point it's a big compromise.

@The Linkage
I can understand why this is not a problem, but the thing is sometimes it is.
For example, barrel length should be the size of a complete path of the bolt traveling through upper receiver. And the delay between hammer striking the primer and bullet leaving the barrel is really big. And e t. c. You may not consider that a problem but I sometimes do.

Then use scripted gas, like my short stroke system on the FAL. My FAL has none of the problems you described here

It works by detecting when the bullet is at the tip of the barrel and activates a thruster

i have tried this system before and the main problem is that if you use the "true blowback" system you do end up with a faster projectile, but you also end up with a much slower cyclic rate of fire, which in tern equates to slower shells and problems with extraction. not that i'm any good with extractors!

i would like to see more gas operation in algodoo so please keep up your work.