Remove ejector for start OAL measurement?

[bkwapisz]

I have read and reread Tresmon's great writeup for load development stickied in the Handloading section. I have purchased and/or fabricated pretty much everything I need to begin trying to handload precision ammo. I am, ubnfortunately, stumped by the first step. I want to measure for my start OAL and have the cleaning rod/stops at the ready. Where I am stumped is this: With the start/dummy round loaded and the bolt GENTLY closed and held with a rubberband around my scope mount, it doesn't seem like there will be enough pressure to compress the ejector spring and I am afraid that I will get erroneous readings because the cartridge is not seated against the bolt face. Can anyone please shed some light on this for me? Is this a legitimate worry, or did I miss something totally? I must've read that sequence a hundred times and maybe I'm just missing the point somewhere.

Thanks in advance for any help.

Brian.

 

[ejb]

Re: Remove ejector for start OAL measurement?

i'd ask tresmon in his thred he would be the one to ask for the answer . i would think it would be depresed by then .

 

[Fuzzball]

Re: Remove ejector for start OAL measurement?

Given that I'm only going to use the max length as a starting point and back off that at least 5 thou for my load testing it hardly seems relivant to get OAL to just touching the lands. Meaning I don't bother with esoteric ways to get that length 'right' to a tenth of a thou. YMMV.

 

[EMorr]

Re: Remove ejector for start OAL measurement?

Just make sure that your cleaning rod is not touching the ejector when you take the first measurement and you will be fine. The second measurement with the bullet resting on the bolt and held in place with a rubber band is simulating a chambered round with the bolt closed and an OAL with the ogive just touching the lands. It seems counter intuitive at first but if you think about it really hard, it makes sense. As an example if you removed your ejector and the case moved back 0.2 inches and the case head is now sitting flush with the bolt face. The whole bolt assembly and bullet would now be free to move forward 0.2 inches until the ogive again contacts the lands of the barrel giving you the same measurement.

 

[oldfatguy]

Re: Remove ejector for start OAL measurement?

Hornady Lock-N-Load gauge works very well. No bolt involved so the ejector is a non-issue.

OFG

 

[bkwapisz]

Re: Remove ejector for start OAL measurement?

I think I'm starting to see it now. The bolt face distance is replaced by the base of the cartridge in the measurement in the second step, or so I understand. We're assuming that the cartridge is fully seated into the chamber when rubber banded shut and that actually closing the bolt doesn't push it further into the gun, no?

 

[DubGunner]

Re: Remove ejector for start OAL measurement?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oldfatguy</div><div class="ubbcode-body">Hornady Lock-N-Load gauge works very well. No bolt involved so the ejector is a non-issue.

OFG </div></div>

Agree with this.