Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Pastimes : Don't Ask Rambi -- Ignore unavailable to you. Want to Upgrade?

To: nihil who wrote (20057)	3/24/1999 12:26:00 PM
From: Jacques Chitte	Respond to of 71178

All else equal - a heavier projectile exits with lower energy but greater momentum. Recoil is a momentum effect. A longer barrel in the same chambering decreases felt recoil even though muzzle velocity goes up. Here's the key to this paradox. Recoil is the sum of kickback from two types of reaction mass. 1) the bullet, and 2) the exhausting gas from the powder (muzzle blast). Item 2 contributes a good deal to felt recoil because while powder gas mass is less than bullet weight, its escape velocity is as high as 5000 feet per second. Thus the mass x velocity term is significant. In a short barrel, there was less time to transfer momentum from the charge to the slug. Also a longer-barrelled arm is heavier, converting recoil impulse into a lower and more manageable backward velocity. A shove is more tolerable than a punch - even if they are equimomental.

To: nihil who wrote (20057)	3/24/1999 4:42:00 PM
From: Ish	Read Replies (1) \| Respond to of 71178

<<Isn't the explosive force completely dependent on the powder and the speed of combustion? i.e. independent of the mass of the projectile? The more massive the projectile, the lower the velocity caused by a given charge. I think. >> You think right. The explosive force is independent of the mass of the projectile. However the recoil is mostly dependent on the mass of the projectile. Load three muzzle loading rifles with 95 grains of FFg powder. Load a paper wad in one making it a blank - no recoil. Second load a 150 grain miniball and you will feel recoil. Third load a 300 grain maxiball and you will feel even more recoil. The three explosions are identical. The explosion creates equal force in all directions. The sides cancel each other as does the top and bottom. With the blank there is no restriction at the muzzle end, so 0 pressure and the opposite reaction is the recoil which is 0. With say the 300 grain Maxi you are building about 1600 foot pounds of energy and the opposite reaction is the recoil. Now that is spread over the entire time the ball is in the barrel and absorbed by the weight of the gun overcoming inertia so the felt recoil is probably about 10 foot pounds.