Sweet... is the best way to create an online account and order online?
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Sweet... is the best way to create an online account and order online?
on the domestic side, the mold is an NEI 458-645-GC, #351.
Given how few are floating around, unless you have a specific known source for the mold, probably just as easy to order from CBE. Certainly faster.
Oh, and at <1000 fps these things don't recoil hardly at all
Why do I think you are lying about the recoilOriginally Posted by Whiterabbit
on the domestic side, the mold is an NEI 458-645-GC, #351.
Given how few are floating around, unless you have a specific known source for the mold, probably just as easy to order from CBE. Certainly faster.
Oh, and at <1000 fps these things don't recoil hardly at all
Totally up to you, happy to go with whatever is the easiest way for you.
You can order it online, or send me an e-mail, either way, same result!
DC
I dunno, the smiley face made me trust him instantly. He seems sincere...Why do I think you are lying about the recoil
OK so $184.50 is it shipped. I will be contacting you in a few weeks then.
You are absolutely right. He must be a big guy. Thats all I can say..
that smiley is what you will look like after pulling the trigger on one of those bad boys.
Seriously though, recoil energy is 1/2*mv^2. if you halve the bullet speed, you drop the recoil energy by FOUR! We know that perceived recoil isn't all that related to numbers, but the point is still there. The recoil you have to deal with is linear to bullet weight, and exponential to speed.
Like I told my gun club. I like shooting anything that involves a big bullet moving slow. Just feels.....civilized.
(6'3" and 145 lb. I blow away in the wind unless I turn sideways....)
Man your a big boy.. lol I am only 6'7 320lbs. I have to be careful on windy days..
To be Honest I have never really shot any big bullets slow. I have shot winchester 510 gr soft points and hornady and remington 500 grain solids all factory.. that is all I have shot out of it.
Actually, the formula quoted is for muzzle energy, not recoil energy. Perceived recoils is much
better described by momentum rather than energy, and the momentum is a direct function
of velocity, so expect the perceived recoil to be proportional to mass times velocity, not mass
times velocity squared. The momentum of the ejected gas is usually included in these calcs
too, as they become significant - the calculation puts the boolit plus powder weight as the total
ejecta, but each has a different velocity - the gas being higher.
Simplified, short version -
405 gr x 1750 fps = 709,000 (rounding to nearest 1000)
720 gr x 1300 fps = 936,000
expect the second load to feel like about 32% more recoil. Personally, my absolute upper limit
with the 405 was about 2100 fps, which works out to 850,000. So, I'd rather not shoot a 720 gr
at 1300 fps, thank you!
In any case - muzzle energy is mostly a useless number - it does not relate well to killing power
or to recoil of the gun, so while it is an accurate mathematical calculation of the energy that
the boolit carries - it doesn't mean much in the real world.
Does the twist in a std .45-70 stabilize this long a boolit properly?
Bill
Last edited by MtGun44; 02-21-2014 at 11:08 AM.
If it was easy, anybody could do it.
well, the formula quoted was for free recoiling energy. In my experience, NOT holding things equal (ie not loading to the same pressure or the same RPM or the same stability factor, since we strive for target accuracy, which may lead to 'incomparable' loads when changing bullet weight), light bullets in fact do show more perceived recoil in the same gun.
But I digress. Wasn't talking about bullet - muzzle energy, was talking about free recoiling energy. I and many others do understand that does account for the bullet weight and the powder charge weight and why.
I and most others also understand that muzzle energy doesn't not equate to killing power or felt recoil, which is why it was not used.
http://www.saami.org/PubResources/GunRecoilFormulae.pdf
Anyways, perhaps unimportant discussion for this thread. I shouldn't have brought it up.
Last edited by Whiterabbit; 02-21-2014 at 12:30 PM.
OK You & Mtgun44 are talking stuff & for us "ology" majors way out of our league.
I don't know what all that means but I will tell you that shooting the same bullet at the same speed with one round out of a straight wall case & one out of a bottle neck - the bottle neck will "kick" more; period!
You shoot a 500 gr out of a 460 at 2500 & a 500 out of a 450 Watts at 2500, the 460 will knock the **** out of you & the 450 is manageable.
And the more "overbore" a case is e.g. a 378 Wby vs a 375H&H, same bullet, same weight, the 378 is much harder. In fact, in felt recoil the 378 can fell worse than a 460. That's why the more overbore a cartridge the more benefit a muzzle break provides with the 300, 338 & 378 Wby providing the most reduction.
In addition, if you take that same 500gr bullet & replace it with a 400 with the same powder charge, on paper its a 20% reduction but felt recoil reduction is greater. That 500 at 2500 hurts, the 400 at 2500 is not a problem.
Now youall probably said that in your posts above but I wouldn't know.
Tom
Thanks for posting your experience on that
I've got a 585 Nyati myself and shoot 900 grain cast bullets from it at around 1700 fps. I also shoot 750 grain Woodleighs at 2250 fps, the Woodleighs are much nicer to shoot than the cast bullets.
Yet on paper for muzzle energy, the cast loads are much lower. I think it's got something to do with trying to launch heavy bullets!
DC
1/2 M V^2 (now muzzle energy, not free recoiling energy, but energy is energy!
That's what MtGun44 meant when he said we cannot compare muzzle energy to felt recoil when he mistook my mentioning free recoil energy for muzzle energy. That we cannot "technically" compare free recoil energy to felt recoil also I mentioned myself in my initial post.
I have examples too! in my 460, I can launch a 740 grain bullet at 930 fps, and a 200 grain bullet at almost three times the velocity. The 740's are civilized, but the 200's are downright brutal. So, two examples that contradict in (muzzle)energy vs recoil.
neat stuff.
1/2 M v^2 is the formula for kinetic energy. If you use the mass of a boolit and the velocity of the bullet at the
muzzle, it is muzzle energy. This is pretty straight up physics. I don't really know the proper definition of
"free recoil energy" so can't make a comment. Depending how you want do define what you are taking the
mass of and what you are taking the velocity of - boolit or rifle, the answers are very different.
In any case, perceived recoil has as much to do with the weight of the gun and shape and size of the stock as
it does the load. Frankly, no simple math calculation seems to do any real justice to matching the
percieved recoil. A lot of it is totally subjective, too. MUCH voodoo in trying to "calculate recoil" and not
a lot of really good science. Lots of folks have their pet method, but different shooters will agree or
disagree which gun and load kicks more, regardless what some numerical value says.
Two guns of identical weight shooting identical ammo will have a massively different perceived recoil with
different stock drop and comb shape. Any mathematical system will tell you that the recoil is identical,
but shooters will not agree with the math. Therefore, the math is not useful, however elegant the
physics and math might be.
The term I prefer is "perceived recoil" because that is what the shooter FEELS, and most calcs do not
do a very good job of matching it. In GENERAL, momentum calcs seem to do reasonably well, but I still
think that they fall short a lot of any capture of the stock shape effects and shooter body type and size.
Bill
If it was easy, anybody could do it.
Wow! Happy I fould this thread!. CBE has the mold I want!
512-975GC Single Cavity
Price: $149.00
Attributes: Gas Check
Other features:
Select:
Special Order 50 BMG or 500 Whisper design. - A Top Punch is available for this mould. Please order in the 'other features' drop down box above.
Qty:
NEI I believe is the mould maker for the 730. I have some from Matt's bullets cast.
NEI has been worthless since Walt died and is now out of business, I believe.
Wayne the Shrink
There is no 'right' that requires me to work for you or you to work for me!
NEI has finally closed their doors.
Old enough to know better, young enough to do it anyway!
Men who don't understand women fall into two categories: bachelors and husbands!
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