Buffer: Circle vs. Square

[Paladin601]

 

 

 

 

I welcome any opinions on any topic, as long as people don't start screeching at me like an angry fishwife.

 

If someone points out a mistake on my part, I figure they did me a big favor. I'm not too proud to take correction when it's offered.

 

This is actually a real good topic, who knows, maybe someone will come up with a miracle buffer.

 

The problem with this topic is there is no data and there are a lot of unknowns.

 

The way the bolt jerks around in there makes it hard to even come up with a comparative or qualitative statement.

 

The only thing i can come up with to say at this point is that the bolt has about 20 ft-lbs of energy and that's not a lot, it's practically nothing.

 

The gunpowder has about 1000 ft lbs of chemical energy, about 400 gets used to propel the bullet, the bolt picks up around 20, the rest is lost to the air as heat.

 

That's not very much energy, it's hardly anything. You arm can deliver about 17 ft lbs of energy with a 1 lb hammer.

maybe a Buffer made of "Flubber" or super ball material?

 

 

If you really want to make a change in the force on the receiver, you need to make the buffer much thicker.

 

The neoprene buffer that we use now only probably compresses by 1/100th of an inch. You want something that is thicker and squishier.

 

The problem is that squishy elastic materials dampen out a lot of energy, turn it to heat.

 

I would not make a real thick neoprene buffer, you'll just jam the bolt to a stop sooner and use the recoil spring less. The recoil spring is your friend.

 

Why not denser ?

 

 

what you're trying to do is lower the accelleration force on the bolt

 

if you lower the force on the bolt, you lower the force on the receiver.

 

the softer (or weaker) that the spring is, the more it will compress when the bolt hits it

 

the more it compresses, the longer time it takes for the bolt to stop

 

the longer time it takes for the bolt to stop, the lower the force is

 

 

if you were bungee jumping, would you want to use a real stretchy bungee cord that took 30 seconds to slow you to a stop, or a real stiff one that jerked you to a stop in one second?

 

same job, different amount of force used

 

the weaker bungee might take 100 feet to stop you, but the stiff one only takes 2 feet.

 

 

so if you want to stop the bolt with less force, you need a thicker buffer that's made from softer material.

 

The ideal thing would be to use a stiffer recoil spring that stops the bolt 1mm away from the buffer

 

because that way you have the whole length of the bolt retraction to stop the bolt, a nice smooth decelleration

Thanks Buzz, that makes sense.

[dalbert]

I approved 3 postings by Scrambles, posted around 1pm today, because I think Buzz and others will want to see them.

 

Scrambles,

 

Keep it substantive and polite if you want to continue posting here.

 

David Albert

dalbert@sturmgewehr.com

[dalbert]

I just saw another post by Scrambles that went to the moderation queue, and have reconsidered my decision to give him another chance.

 

David Albert

dalbert@sturmgewehr.com