Can someone explain barrel diameters v. rifling to me? Because

thats exactly what i'm sayin

The tolerance isn't that precise, the bullet is a little loose, and when it fires the rear expands into the grooves.

>>734408008
>Can someone explain barrel diameters v. rifling to me?
==> /k/

high point is .446in diameter

.004 isn't enough room, you want the bullet to move not get stuck.

I think I am correct, I know my math but I don't know barrel physics at all.

>>734408127
I'm working with a .001in granularity, but you're saying that it's usually not measured that precisely? There's no significant mechanical effect due to bullet deformation?

I'm asking because I feel like there might be a noticeable pressure difference depending on which of those two you land on.

>>734408285
Okay I think I get you.

To recap, I should assume a .450in bore, consider that .454 high point an offshoot covered in a tolerance range, and then apply a .004in groove to .446in depth?

>>734408322
I'm saying a mfg will not be within +/- .001
Maybe like = .001 - .005

>>734408496
+.001

>>734408470
>.454
>.446
Got those two switched around but you get my point

>>734408496
I can produce it with 25 micron granularity without any tooling that might affect it.

>>734408582
And I could open my gun cabinet and measure boxes of ammo that are within a few thou of their nominal calibur.

>>734408691
I see, so at that scale the difference becomes negligible to the result?

Don't have too much time to respond as i'm at work but have a look a the SAAMI data for .45. SAAMI info can be found in this document:

http:// saami. org/specifications_and_information/publications/download/Z299-3_ANSI-SAAMI%20_CFPandR.pdf#page=10

From a brief look through the document, pages 45 and 168 may contain the info you'r after.

>>734408929
Thanks, I'll dig through it. You guys have been very helpful.

>>734408794
Nah, I think there's a measureable difference. Just depends on your use case.

Me shooting steels with a 50 year old 22LR I really don't give a shit.

Holy shit this thread is in English but it's almost as if it's a different language

>>734409043
Nah it's still in English, you're just ignorant on the subject matter.

>>734409031
Well I was mostly worried about jamming the thing if I cut the diameter short.

The use case is I'm experimenting with designs, so I'm really digging into these details for the first time. But I'm looking to create some test models to run an analysis. I guess I should be testing the full range but I didn't want to make design flaws out of the gate.

>>734409205
lol just use more powder!

Go measure your bullet and build to the type. You need it to seal against the bore, so if your projectile doesn't have an expanding tail section (do modern bullets even do that any more?) then you'll have to cut the groove to the bullet diameter and probably a thou under. The height of your rifling differs for jacket material.


Frankly, don't reinvent the wheel until you know why everyone for the last 2000 years has built guns the way they do.

>>734409654
>Frankly, don't reinvent the wheel until you know why everyone for the last 2000 years has built guns the way they do.
That's why I'm here

>>734409719
Isn't there a book about this?

>>734409205
>experimenting with designs

I figured you were trying to do something that wasn't covered in a book.

>>734409881
>I figured you were trying to do something that wasn't covered in a book.
Honestly I'm such a greenhorn to this subject I needed people more familiar with guns to give me something to hook onto first.

The best I got so far was a document that *is* jampacked with machining diagrams for the 1911, but the original question wasn't clear to me yet. The info you guys have given me helps.

>>734409881
Yes
Reloaders Bible

>>734410237
Well I watch a lot of how it's made, so I am basically an expert, and I'm just googling the answers for you.

>>734410342
I slept at a comfort inn.

File: Doubt.jpg (27KB, 492x280px) Image search: [Google]

27KB, 492x280px

>>734410539

>>734410539

Well, aparently you haven't learned anything, Its "I stayed at a Holiday Inn Express last night"

>>734410872
Disgusting normie. GTFO!

>>734408008
It's measured at the chamber. The riflings grip into the lead.

>>734408008
nigger we have a board specifically for shit like this

>>>/k/

>>734408008
if you want a thorough answer i'd strongly recommend going to >>>/k/