.308 Win . What is your chamber size ?

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narada314

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I am trying to figure out how deep to push bullet with my reload (Hornady 168gr, lapua brass for 308 Win).
I found video to measure chamber length using cut on size brass and "over jammed" bullet.
You chamber it, rifle will push bullet inside, you get it back and measure it again.

Using this method I measure chamber length of my .308 Win

I got following numbers in inches: 2.950, 2.955, 2.953, 2.953

Did anybody measure actual chamber length on .308 Winchester ?
What is your numbers ?

It looks too long to me (there is a little chance that I read caliper wrong).

And second question:
If my chamber size is 2.950 and I want to place bullet at 0.002 this means case over all length should be 2.930. This is too long, I am not sure bullet even will hold on to the brass.

My last COL load was 2.800 (as reloading manual suggested).

Can anybody help me out with advice. What I understand wrong ?
 
2.950" minus .002" is 2.948. I am thinking you mean seating the bullet .020" off the lands which would put you at 2.930". Measuring the OAL is a waste of time as bullets do vary in length even from the same lot #. Are you using 168 BTHP Hornady bullets or 168 Amax bullets?

I have found that just about every bullet works well .020 off the lands except to VLD's bullets that like to be jammed.
 
A couple of thoughts:

What rifle is it? Hunting rifles can have long throats- and what you have could be just a long throat.

1) is the bullet being pulled out of the case when you extract it? jamming it into the lands will cause it to stick so it could be being pulled back out of the case when you extract the case. I have found some success at pushing the bullet/case back out using a cleaning rod (remove the extractor from the bolt). The lengths you mention seem too long.

2) as stated, OAL is not very useful other than to fit in magazines. Get an ogive comparator so you can measure the base to ogive length of your loads. This will be the location where the bullet touches the lands and will give you comparable results between bullet lots and even different bullets.

3) it is not easy, but another method is to chamber a dummy round (no primer/powder!!!) and push a cleaning rod down the barrel. Make a mark on the rod. Remove the dummy round and push a bare bullet into the chamber until it touches the lands. Push a cleaning rod down the barrel again and make a new mark. The difference in these marks is the distance to the lands compared to your dummy round.

4) Hornady makes a gauge that uses a dummy case. I've never used one but it looks slick.

For what it is worth, in my .308 the distance from base to ogive is 2.236" (at the moment- it recedes with erosion) and I load to 2.221" for a 0.015" jump using the same bullets you are using. Measuring my hornady 168gn dummy round gives a COAL of 2.823, but again, this is mostly a useless measurement.
 
My rifle is Remington 700 SPS Varmint .308 Win .

1. bullet was not pulled out. it was pushed into brass. COAL before I chamber it was 3.000

2. I am not using magazine (I load rounds by one - shooting from table)

3. I saw that method on youtube also. Will try it this week.

I will investigate this more before I moving out of COAL recommended by manual.


THANX FOR ADVICES TO ALL !
 
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