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JLF
03-06-2022, 12:30 PM
I am going to buy a mold at Accurate Molds.
This is the bullet model I want to get:
https://i.postimg.cc/XJNm0YMp/34-250-B-D.png (https://postimg.cc/HJKBwHkg)
The mold is made of iron to obtain two bullets.
Is there any measure that I should take into account that depends on my rifle?

Nobade
03-06-2022, 12:52 PM
The main thing you care about is the rifle's throat diameter and neck diameter, as in, will it accept a bullet that fits the throat into a fired case? I try to keep bullet diameter no less than .0005" (5 tenths) less than throat diameter for best performance. Otherwise you'll seat it to whatever depth fits your particular chamber.

JLF
03-06-2022, 01:31 PM
How do I take those two measurements?

gwpercle
03-06-2022, 07:58 PM
The main thing you care about is the rifle's throat diameter and neck diameter, as in, will it accept a bullet that fits the throat into a fired case? I try to keep bullet diameter no less than .0005" (5 tenths) less than throat diameter for best performance. Otherwise you'll seat it to whatever depth fits your particular chamber.

Isn't .0005" = to ... five ten thousandths

and .5 = to ... five tenths

I'm no math wizard but just trying to keep JLF (OP) straight , being from Argentina he may not be familiar with our numbering system and just trying to keep him straight ...
five tenths and five ten thousandths might make a difference .
Gary

JLF
03-06-2022, 08:12 PM
Isn't .0005" = to ... five ten thousandths

and .5 = to ... five tenths

I'm no math wizard but just trying to keep JLF (OP) straight , being from Argentina he may not be familiar with our numbering system and just trying to keep him straight ...
five tenths and five ten thousandths might make a difference .
Gary

Very kind of you.
0.0005"=0.0127mm
0.5"=12.7 mm
The measurements referenced by Nobade are the diameter of the chamber and the Maximum cartridge length?

Nobade
03-06-2022, 08:12 PM
Isn't .0005" = to ... five ten thousandths

and .5 = to ... five tenths

I'm no math wizard but just trying to keep JLF (OP) straight , being from Argentina he may not be familiar with our numbering system and just trying to keep him straight ...
five tenths and five ten thousandths might make a difference .
Gary

Sorry, as a machinist I am used to thinking in thousandths. So I see that as five tenths of a thousandth. Anyway, it's really small.

To answer the OP on how to measure the chamber and throat, you need Cerrosafe to pour a casting of it. You can also cut about half of the neck off a case, fill it full of lead, drop a pure lead bullet in the chamber, close the case behind it, and pound the bullet to fit with a close fitting steel rod from the muzzle. This method is sort of risky but the resulting pound cast lasts forever. A Cerrosafe casting is only accurate for a short time so it's not any good for filing away for future reference but easier and safer to make.

Bigslug
03-06-2022, 08:49 PM
Link to the forum's sticky on how to pound cast: https://castboolits.gunloads.com/showthread.php?356251-Pound-Cast-instructions-(for-rifle-chamber)

bigboredad
03-07-2022, 08:31 PM
The easiest thing to do is email Tom he can tell you exactly what you need and how to get there

Sent from my SM-T377V using Tapatalk

dh2
03-07-2022, 11:28 PM
I would use a very simple method base on my experience dealing with accurate molds, Slug the boar on your rifle, send Tom at accurate a message telling him what you are after and let him take it from there, I have been happy with the results every time

243winxb
03-08-2022, 09:49 AM
Groove diameter + .0015"

JLF
03-08-2022, 09:20 PM
How do I get in touch with Mr. Tom?

Nobade
03-09-2022, 09:11 AM
How do I get in touch with Mr. Tom?

www.accuratemolds.com

JLF
03-16-2022, 11:42 AM
I already emailed Tom.
I appreciate everyone's help.

truckjohn
03-16-2022, 07:13 PM
I would also verify the distance from the crimp groove to the leade in your gun. Jamming bullets into the rifling doesn't always go to plan, especially if you need to extract a loaded round.

Another dimension off your gun is the nose diameter. It looks like a slight step down from the front band - perhaps a bore riding nose. Verify that this will go in the gun via pound cast.

Dragonheart
03-19-2022, 02:17 PM
The first thing I would ask if I were ordering a custom mold is will you make it a nose pour mold? As for the dimensions a bullet size the bands to fit the barrel groove and the nose to fit the lands should provide the best accuracy. This is the reason most find a bore rider design the best choice for long range accuracy. I would do a chamber impression first and slug the barrel to obtain the measurements you need. If you intend to powder coat then under-sizing the bullet to allow for build out and reducing the amount of metal moved should also help with accuracy.