Quickload predictions of case capacity

[A5BLASTER]

Who here k owns how to work and tweak quickload?

Had a wild idea get in my head last night and need a question resonibly answered. Just for fun ofcourse.

What would be the predicted useable case capacity if we stretched the grendel case and gave it a OAL length of 1.610 with let's say a COAL length of 2.290 inches.

[CJW]

I bet you Klem has Quickload

[grayfox]

Is this like make new brass that length but keep the same shoulder and neck dimensions? As in a - sort of - super grendel 0.1000 longer case length?
Not simply blowing out the grendel case and leaving what's left to be shoulder and an obviously shorter neck...

[grayfox]

An extra 0.100" in case length (therefore also in chamber length since the horizontal cylinder of the case is longer), assuming the shoulder and neck dimensions don't change, would yield about 6.6% more available volume, by my back-of-envelope calculations. This leads to about +2 grs powder capacity.
Now we must assume a bolt action b/c an AR bolt limits us pretty much to the 52Ksi developed pressure... extra powder means extra pressure possible... so a bolt action can be made to handle that.

Also I would assume that the extra coal does not add a significant amount of performance (just less case-volume robbery by the bullet), this is of course a simplifying assumption.

What would an extra 2 grs of powder do to the developed MV? Using 123 gr Eld's/SSt's & CFE as an example (also 24" barrel), it adds about 160 ft/s to the final MV. I got the same theoretical increase with 2520. Since the case volume has been expanded I'm assuming that final pressure is still within limits.

Now all of this is without using QL, so when the QL experts chime in I will be interested in what they can advise.

[JASmith]

Vongruff did something similar. This one thread discussing the Grendel Max:

http://www.65grendel.com/forum/showthread.php?3002-Bolt-rifle-for-dedicated-handloaders&highlight=Grendel+Max

[A5BLASTER]

Is this like make new brass that length but keep the same shoulder and neck dimensions? As in a - sort of - super grendel 0.1000 longer case length?
Not simply blowing out the grendel case and leaving what's left to be shoulder and an obviously shorter neck...

Yep just stretched out.

[A5BLASTER]

Vongruff did something similar. This one thread discussing the Grendel Max:

http://www.65grendel.com/forum/showt...ht=Grendel+Max

Vongruff pushed the shoulder forward.

I'm talking about making the whole case 100 thousands longer.

Everything the same but longer by 100 thousands.

[A5BLASTER]

An extra 0.100" in case length (therefore also in chamber length since the horizontal cylinder of the case is longer), assuming the shoulder and neck dimensions don't change, would yield about 6.6% more available volume, by my back-of-envelope calculations. This leads to about +2 grs powder capacity.
Now we must assume a bolt action b/c an AR bolt limits us pretty much to the 52Ksi developed pressure... extra powder means extra pressure possible... so a bolt action can be made to handle that.

Also I would assume that the extra coal does not add a significant amount of performance (just less case-volume robbery by the bullet), this is of course a simplifying assumption.

What would an extra 2 grs of powder do to the developed MV? Using 123 gr Eld's/SSt's & CFE as an example (also 24" barrel), it adds about 160 ft/s to the final MV. I got the same theoretical increase with 2520. Since the case volume has been expanded I'm assuming that final pressure is still within limits.

Now all of this is without using QL, so when the QL experts chime in I will be interested in what they can advise.

What if I told you with a case length of 1.610 you can run any bullet from 129 ablr and lighter at 2.290 and mag feed.

Either way it is just playful thinking and wondering.

[grayfox]

That's where I figure you're going. Essentially it's a case that is just longer than the std Grrr by 0.100" but keeping coal under 2.300....... bullets in mind I was guessing probably 123-129...
I still would estimate that you're talking a bolt action vice AR, I'd guess internal pressures go up to around 55,000-58,000 psi (all guesswork mind you! Where are you QL guys!!!)... so well within a std bolt action which the short action handles 58,000-62,000 psi in 6.5 Creed, 243 Win, 7mm-08, etc, 308...

Kind of a mini-Creedmoor but maxi-Grendel.

If you get ~+160 ft/s with this new case, does that get your MV up to where you want?

[grayfox]

I down-load some 123's and 129's in one of my Creedmoor's to around 2700+ ft/s to make mild loads, and they're on a node so accuracy is good. I'd figure that's about where you might max out in your maxi-Grr. I get to use Varget and H4350 w/ no worries, even XBR etc etc in that case, so those are powders I have and use a lot.

Varget about 35-36 grs for those loads if I recall... Your new case would top out at maybe 34-34.5 grs. So not a lot of difference there either. Any QL guys might know which powders you'd need to run in this new case.

[A5BLASTER]

That's where I figure you're going. Essentially it's a case that is just longer than the std Grrr by 0.100" but keeping coal under 2.300....... bullets in mind I was guessing probably 123-129...
I still would estimate that you're talking a bolt action vice AR, I'd guess internal pressures go up to around 55,000-58,000 psi (all guesswork mind you! Where are you QL guys!!!)... so well within a std bolt action which the short action handles 58,000-62,000 psi in 6.5 Creed, 243 Win, 7mm-08, etc, 308...

Kind of a mini-Creedmoor but maxi-Grendel.

If you get ~+160 ft/s with this new case, does that get your MV up to where you want?

Not building anything just got bored and was looking at some cases next too some grendel cases and the thought hit me. What would the usable case capacity be if the grendel case was stretched out too 1.610.

I already get over 2600 with the 129 ablr with the case like it us now.

Hypitically speaking 2700 to 2750 sounds probably right where the accuracy load would be in this dreamed up case with cci450, h4895 and 129 ablr.

[A5BLASTER]

I down-load some 123's and 129's in one of my Creedmoor's to around 2700+ ft/s to make mild loads, and they're on a node so accuracy is good. I'd figure that's about where you might max out in your maxi-Grr. I get to use Varget and H4350 w/ no worries, even XBR etc etc in that case, so those are powders I have and use a lot.

Varget about 35-36 grs for those loads if I recall... Your new case would top out at maybe 34-34.5 grs. So not a lot of difference there either. Any QL guys might know which powders you'd need to run in this new case.

If such a case was real. I would put my money on h4895, h322, ar-comp, aa2520 and tac.

Ofcourse you could still probably get anoutghter 50 fps over those with cfee223, lever, h335 put since I moved on from them in real life I see no reason to use them in my dream case lol.

[kmon]

I wish I still had QL and may go ahead and get it again. The difference you are talking about is about the difference in volume between a PPC case and the Grendel case, now take the tape out of it and that would incease the amount about that much more and for a boltaction that could work well. Now is it worth the $? Only the one spending the $ could say that but the rendel Max gets about as much as you can expect from the current Grendel case. There are brass companies out there that will make brass to your specs, the custom brass costs a lot more than standard factory brass but it can be had.