Trying for more advanced load development.....

[HSPrecision]

But i have some questions... These are all for .308 chambered HS precision

questions are
how does OAL affects chamber pressure?
what is the optimal distance between the ogive to the lands
what is the maximum OAL to feed from a rem 700 action?

im kinda new at this and i want to safely learn to do load development. So i figured i go to the experts.

R/
~2ND

 

[The Mechanic]

Re: Trying for more advanced load development.....

You have until the end of the day. For exactly what you need.
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1293735&page=1

 

[MitchAlsup]

Re: Trying for more advanced load development.....

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2nd Chance</div><div class="ubbcode-body">how does OAL affects chamber pressure?
what is the optimal distance between the ogive to the lands</div></div>

If the OAL is SAAMI, as pressure builds the bullet jumps forward reducing the pressure. The bullet then impacts the rifling with significant momentum and this, in turn, moderates the pressure rise curve during engravement of the rifling on the bullet.

If the OAL is very long, the bullet rests on the lands and the pressure in the chamber has to perform the engraving function. This leads of a sharper rise in the pressure curve and can lead to excessive pressures.

If the OAL is very short, with a normal charge weight, you are compressing the powder. If you actually crush the powder, it can lead to slightly faster burn characteristics and steepend the rise curve of pressure. Generaly the bullet jumping towards the lands will reduce this excess pressure, although it might show up on the primer if the case has a short sholder.

You rifle load development will tell you what the optimal jump distance window is. It will change based on bullet, charge weight, sometimes base on powder choice.

 

[HSPrecision]

Re: Trying for more advanced load development.....

Thanks! that makes sense, I would love to get in on the group buy but since its closing today I'm gonna miss this one. I want to try new things with hand loads but not at the expense of my eyes, fingers or rifle action.

 

[bugman]

Re: Trying for more advanced load development.....

you might want to consider Glenn Zeideker's book.

 

[4Rail_Gunner]

Re: Trying for more advanced load development.....

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bugman</div><div class="ubbcode-body">you might want to consider Glenn Zeideker's book. </div></div>

+1, there is some good things to read in there.