re visiting head space & bullet set.

longbowhunter2

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Oct 16, 2013
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it has probably being over discussed but had to review again because I forget important data.
I believe if reloading it is important to have gage to check the cartridge head space to SAMI requirements.
so I am stopping until can pick up a set of gages for 243 win & 308 win. I looking at Lyman go & no go gage to verify my rounds.
In my business I designed similar gages with cad to verify #1 checked correct taper, and to verify correct length.
but for the price they sell them I could not make them at that inexpensive price. The material alone would cost more.
I reposting this video so any newbies like me under stand this and I suggest buying a set of gages.

I was watching an old guy reloading for years and he explained head space incorrectly, you tube can be very informative. but I have learned from my business to triple verify every thing.

so I pull some standard mfg ammunition's of 243 win, verified the overall length, and although was correct to SAMI spec's, the rounds were all over the place.
next I have a machinist magnetic v block and I will verify the concentricity of case seating surface to the cartridges to the bullet and verify the runout.
it will be interesting to verify the results compared what I can reload.
CAN SOME ONE REMIND ME HOW TO verify THE OGIVE of the bullet TO THE RIFLING. I inserted a dummy round with no primer or powder
into the chamber with the bolt locked and the OAL was way longer than the standard ammunition, that is crazy
and maintain the SAMI over all length of the cartridge. according to the old timer for safety never exceed the bullet diameter length.
in other words a 308 win must have minimum .308 seating contact with the bullet to the cartridge length.
any way for safety and I not a bench precision shooter I will stick with SAMI overall length specifications.
do hurt my feelings if any one has constructive advice.
 
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You don’t need go/no go gauges. However you do need to compare your headspace to a fired round. Hornady comparator is a great tool for this measurement. Set your headspace back at least .002. Your resized case needs to measure .002 or shorter than a piece of brass fired in your rifle.
Sammi is simply a reference.
 
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Ugh....
OK so Sammi spec means nothing. Or in this case you don't care. The point of reloading is to make better ammo.

You do not need go no go gauges.

So starting fresh

First to find the lands use the wheeler method for finding lands. Just Google it and watch the videos. This is for bolt guns, for Ar15 pattern guns use the Hornady oal gauge.

Now take a fired case, measure the shoulder with the whidden shoulder bump gauge https://www.whiddengunworks.com/product/shoulder-bump-gauge/
For a competitive rifle set the die to push back. 001, for a hunting bolt gun set it back.. 002 and for a AR set it back 005.

When you seat your bullets start. 030 off the lands to start. Do not jam a hunting gun. Also jamming can spike pressure so be aware.

On a factory chamber don't worry about the body. Factory guns tend to be loose and any die will probably be under sizing your brass. Check the fired vs sized brass.

Uses the whidden videos to help you do all this. They are a great resource even if you don't use their products.
 
Also.... Don't worry about runout/concentricity. There is nothing you can do to fix it with the gear you have and your gun does not care.

Also also... The amount of bullet bearing surface inside the neck won't be a problem on a factory gun shooting normal weight bullets. Only way to get in trouble would be with crazy light projectiles. 200 thousandths is just fine and to get that little you would need a custom throated chamber.
 
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Hi Aeon, Punkur67, and Chris240

great thank you very much for the feed back. and you guys are great. got leads need to follow up. it's all about attitude and willing to listen. which I am doing.
very valuable information.

Respectfully
Lee
 
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alex took his video off youtube and hosted them on his site.. scroll down and watch the video on how to find your lands..... its accurate and repeatable.
 
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I sold most of my old inspection equipment, but retained calipers, set of micrometers 1-3 inch, a sin bar, few drop indicators, machinist v block, couple of flat ground bars, and small plates. indicator holder and a cheap adjustable height gage. few odds and ends, and my original Kennedy box. I used my company supplier equipment before I retired. I miss that.
 
currently have 3 sets of press dies, 243, 270 and 7 rem mag, vibrator tumbler, wax for lube, lee hand press, Hornady beam scale, electric trimmer, powder trickler, have some 100 gr Hornady bullets, and some 243 brass, some more on the way. a lee precision hand primer on the way. i believe all I need now is a 243 head space gage. then I can get started again. phew
 
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just looking at stuff for curiosity

does any one have a print on the chamber for the 5.56 NATO? I pulled the SAMI spec's they supply them for free. I am just curious.
and yes I am aware of the 5.56 will not work for rifles chambered for 223 Rem.
I was looking at the 243 Win cartridge's design and was looking at the stack up of dimensions, wow very wide open tolerance.
from a standard SAMI fire arm and cartridge head space there could be .004 interference to like .013 clearance to the taper of the head space.
no wonder stuff fly all over the place.
 

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Don’t get to far into the weeds here. Keep it simple and have your 223 chambered in 223 wylde, then you can shoot either 556 and 223 with no worries.
Additionally sammi is a reference for manufacturers. All rifles chambers are going to measure slightly different, there are some exceptions.
 
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Don’t get to far into the weeds here. Keep it simple and have your 223 chambered in 223 wylde, then you can shoot either 556 and 223 with no worries.
Additionally sammi is a reference for manufacturers. All rifles chambers are going to measure slightly different, there are some exceptions.
My mini 14 is 223, and my ar-15 5.56. is is possible to have gunsmith modify it to 223 wyle
 

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