Gordens reloading tool vs Quickload

[jxb]

first... yes, i know, zombie thread.

next... i was going to post for any new info relating to 'start pressure' parameter as relates to seating depth, but found this thread.

finally... for a few of the folks i know to be GRT users, is not the parameter affected by bullets either touching, hard jammed, just off etc.?

(all the old reloading manuals caution to reduce loads as coal approaches touch, and indeed long throated chambers with legacy length bullets (the opposite condition) could run 'higher' pressures.)

since GRT does not seem to accommodate freebore length, how do we reconcile?

@Beiruty @jelenko @Straightshooter1

I was reading your post and thought I'd ask Charlie about it since it seemed GRT might account for it. Doesn't sound like it does for necked cartridges and he goes into why. Anyhow below is a link to that conversation and next link is one he referenced in the response that points to a very interesting article, also below.

You all might find this interesting (discord account needed and maybe invite to the channel)
'https://discord.com/channels/621039234404581406/694108252824273046/1252035442585370745'
'https://discord.com/channels/621039234404581406/694108252824273046/1128337876422242448'
That is when the Bullet Jump option comes into play in the simulation.
Reference = Laurie A Florio 'https://www.sciencedirect.com/science/article/pii/S0307904X1200635X'

 

[chop house]

thought I'd ask Charlie about it since it seemed GRT might account for it.

Thanks for info but am not on discord. What is the executive summary?

 

[jxb]

Kinda hard to sum it up as there's a few paragraphs of info, an animation and a link to the other thread which has the link to the sciencedirect doc (which you should be able to view).

I got from Charlie's response that GRT doesn't account for it in necked cartridges, but does straight wall and why, shoulder angle comes into play. Plus in the next paragraph Charlie wrote "In our tests of bullets being seated into the lands, we did not see large increases in pressure in cartridges like 6.5 CM (long tight freebore) unless the bullet was seated to "Hard Jam"" followed by more info, caveats, etc.

Don't really understand it all so best to simply read it oneself as I know there's a few people on here that would not only understand all he's saying but probably all of the Florio doc which most of it is WAY over my head.

Anyone that does or is interested in GRT would be well worth their time and energy to create an account and join the channel as there is mountains of information there and ongoing support for the current product. This is of course where they are also working on GRT NextGen.

 

[chop house]

@jxb
thank you