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So this is why a 9mm 115g has snappy recoil vs a 147g that has more of a 'push', easier to control?
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So did you try to chamber the longer round? Also I never said the head space was off the bullet did I? Throat and Leade and not headspace, but a chamber cut too deep >Headspace issue< will take a longer bullet. Why not use the 30-06' like you said?Since a picture is worth a thousand words (for some, at least), I offer this:
Today's project was wringing out a new .270 for a 13year-old boy in Montana who has chosen to upgrade from a .243. This makes it very convenient (with all the bench dedicated already) to illustrate my previous point. (My deepest apologies that I did not dig out the .30-06 stuff, but the concept is precisely the same).
On the left you have a heavy roundnose bullet (150g). On the right you have a light hollowpoint (90g: sorry it's not a spitzer). Both are seated to the precisely identical depth in the neck.
Unless I am prepared to exercise Foghorn Leghorn's preparatory system for reassembly of my body, I CANNOT charge the case on the right with a near-maximum load for the 90g bullet, and put the same amount of the same powder into the case behind the 150g bullet on the left.
Oh. Another marvelous discovery: Since the .270 is not one of those very special cartridges that headspace on the bullet, both these cartridges chamber in each of three .270's currently at the house.
No charge for this service. Drive Safely.
think of it this way when it comes to powder and bullet weight
a 100 lb man pushing a cart that weighs 100 lb will need X amount of ummph to get cart to move
if the 100 lb man needs to push a cart that is 500 lb if he used x amount of ummph to try and move the cart
he would hurt himself by using to much presure to move heavy weight to fast
so if he used y amount of umph one m less and he took just that one m longer to get the same pressure
the 500 lbs would then start to move auntill it reached the same as the 100lb cart
I began posting in this thread with a reference to the Warner Bros. cartoon character, Foghorn Leghorn, and his proud technique of being able to recover from any disaster (explosion, etc.) by having his "feathers numbered for just such an occasion" (for restoring himself to health to continue the episode).
It took 23 posts, but somebody on this thread finally used the right word: inertia. Not bullet mass - its inertia.
Those other considerations like friction may be significant under some circumstances, but doesn't peak chamber pressure occur very early in the burn? Like very, very early? That clearly means the biggest effect is the inertia of the slug.
But anyway - I want to ask the Assembled about a different but related problem: loading for the quietest possible cartridge.
Say in a .45 carbine with a 16" barrel, couldn't I use a very light load of a fast powder, stay within the peak-pressure limits, and get a more complete burn and a greater fall-off in gas pressure before the bullet crowns? I know I'd give up a lot of muzzle velocity, but the goal is to get the gas pressure as low as possible at the moment of crowning, so that the suppressed signature is minimized.
Waddya think?
Since a picture is worth a thousand words (for some, at least), I offer this:
Today's project was wringing out a new .270 for a 13year-old boy in Montana who has chosen to upgrade from a .243. This makes it very convenient (with all the bench dedicated already) to illustrate my previous point. (My deepest apologies that I did not dig out the .30-06 stuff, but the concept is precisely the same).
On the left you have a heavy roundnose bullet (150g). On the right you have a light hollowpoint (90g: sorry it's not a spitzer). Both are seated to the precisely identical depth in the neck.
Unless I am prepared to exercise Foghorn Leghorn's preparatory system for reassembly of my body, I CANNOT charge the case on the right with a near-maximum load for the 90g bullet, and put the same amount of the same powder into the case behind the 150g bullet on the left.
Oh. Another marvelous discovery: Since the .270 is not one of those very special cartridges that headspace on the bullet, both these cartridges chamber in each of three .270's currently at the house.
No charge for this service. Drive Safely.
I would also ask your input as to whether mass is a significant factor in inertia. (Actually may be the root in some cases: I believe it is).
Deadshot to the rescue again. (With one clarification):
"Headspace is a measurement from the case head to a datum point on the shoulder"
I submit to add to Shoulder: Belt (in case of a belted--magnum?--case), or in some cases, the mouth (.45ACP).
I think we can add rim, too.? for some examples??