Did Hodgdon screw up or are we missing something

[BluteEhre]

Have to ask, since this info has me scratching my head.

I think we can all agree Hodgdon has crapped the bed as far as helping us really get the most out of reloading this cartridge.

While looking at the 2021 Hodgdon Annual Reloading magazine I noticed they list data for the 6Arc cartridge(basically a 6ppc) which is also basically a 6mm grendel. With this cartridge they tested the usual suspects of powder we all would expect BUT they also have data using 6.5 Stabil. This is what blows me away.

This powder is slower than imr4350 and falls just faster than Reloader 19 on their burn rate scale. What in the heck.

Are we missing out on a few powders that should work well with the Grendel(slower than CFE and LVR) or did a tech at Hodgdon screw up thinking it was a good choice for such a similair cartridge.

I see they list this powder in .223 under a 77gr MK. So odd.

Perhaps theyre trying to tell folks like myself how to use it up after believing their claims of how great speed it could achieve in 7mm-08. Only to find they were completely full of crap..unless life and limb wasnt important to the reloader.

[lazyengineer]

smaller diameter bullet and boresize.

The larger the bullet diameter, the faster the reaction chamber vessel increases in volume as the bullet moves down the barrel, the faster the gunpowder burn rate you need to keep up.

Conversly, the smaller the diameter, the less the reaction chamber volume increases with time, and the slower powder burn rate you need since the reactor chamber volume is not increasing as quickly with time.

[LRRPF52]

[BluteEhre]

I understand where you guys are coming from. But the 6ppc is listed with almost the exact powders they tested the grendel the 6arc(almost identical round)is listed with powders "we" know are great in the Grendel and then they throw in 6.5 stabil which is a long ways down on their burn rate chart and definitely slower than what people runs in a .223 as well. Seems as they are either off a bit on the actual burn rate or they are trying to prop up a powder that has left many people disappointed.

[LRRPF52]

Hodgdon is pretty conservative about what they publish, and base that on instrumented pressure test breech research, not marketing.

For example, they have not published data for CFE223 and 6.5 Grendel, but Hornady has been doing so for some time (since the 9th Edition).

Also notice that they publish Varget data for some of the lighter bullets in 6mm ARC, which is just not a thing in 6.5 Grendel. Reason?

Because you can build pressure more optimally in the 6mm ARC with slower-burning propellants than you can in 6.5 Grendel, making some not suitable for Grendel, but ideal for 6mm ARC.

I seriously doubt they would approach recommended powders from a marketing standpoint, since demand for powders is higher than ever right now.

Bore ratio makes 6mm ARC a different ballgame compared to 6.5 Grendel from an internal ballistics perspective.

[BluteEhre]

Guess we will leave it to the 6mm Arc guys to figure out why they didnt bother publishing data for H380,imr 4451,the 4350's and hybrid 100V and jumped down to 6.5 Staball.. and the .223 guys must be just as perplexed. Maybe I will try theyre starting load for the 77gr bullet in .223. Would love to use up some of this stuff.

[StoneHendge]

I bought some 6.5 StaBall to try in my 6.5CM and couldn't get decent SD's. I had no other use for it so I tried it in my 243 LBC with some 105 Matchburners in a converted Large Primer x39 case and basically ended up with Varget like speeds. I actually had decent accuracy with a mild charge (2400 fps or so out of an 18") and ended up buying another pound to use up my bullets as a practice round. I don't know if the larger "spark" from the LP had an impact but it did surprisingly work. Nothing I would go out of my way to use, though.

StaBall is made in the US and has been quite available. Probably why Hodgdon did data since it can "work".

[BluteEhre]

I found they are way off on their posted speeds in the 7mm-08 and I had pressure signs at their mid range charges. Seems like others were getting the same experience in that cartridge. I consider it kinda similiar to CFE Black... in regards to it being a powder that never needed to be.

[LRRPF52]

When I loaded for 7mm-08, everything was textbook. I was using Hornady data for the 139gr GMX though.

[BluteEhre]

You actually got their claimed ~200fps speed increase over other powders? Certainly would make the copper bullets work beautifully. Maybe I got a poor batch, in a long throated remington i was getting sticky bolt and stiff extraction way early on in load development as well as large ES.

[LRRPF52]

[Mark611]

just my thoughts, a lot of the load data out there with powders listed for the 120 and 123gn bullets for the 6.5Grr, theirs's none of these powders that come close to the published data from my barrels for their lengths, my 18'' 1in8 with 28.5gn of AA2520 for example comes in around 2280 ave, Hornady's manual shows 2400fps from the same barrel length, along with the H322, H4895, and a few other powders I have tried, just saying! I'm just chasing my tail, so as I have said and a few others you need to develop a safe load using your own development for the 6.5Grr, I don't like that! IMO there should be a powder that works as advertised or as close to it as possible IMO without the tail chasing! I'm a reloader of many cartridges and this 1 has a lot of work involved to get what factory Hornady Black does out of the box as far as velocity is concerned! JMO

[LRRPF52]

just my thoughts, a lot of the load data out there with powders listed for the 120 and 123gn bullets for the 6.5Grr, theirs's none of these powders that come close to the published data from my barrels for their lengths, my 18'' 1in8 with 28.5gn of AA2520 for example comes in around 2280 ave, Hornady's manual shows 2400fps from the same barrel length, along with the H322, H4895, and a few other powders I have tried, just saying! I'm just chasing my tail, so as I have said and a few others you need to develop a safe load using your own development for the 6.5Grr, I don't like that! IMO there should be a powder that works as advertised or as close to it as possible IMO without the tail chasing! I'm a reloader of many cartridges and this 1 has a lot of work involved to get what factory Hornady Black does out of the box as far as velocity is concerned! JMO

[Mark611]

Both of my rifles are Type11 bolt/chambers, I'm using a Beta CHRONY set 10' from the muzzle, sometimes I use my brothers Lab Radar, my powder charges are weighed on a A&D HR-100AZ Lab scale backed up with an old Redding beam scale, so I know my charge weights are correct, my seating depths are just a tic under mag length, my bullets a lightly crimped with a factory crimp die, I know my CHROY is working correctly because I shoot other calibers along with the Grendel and their velocity's are right where they should be!

[LRRPF52]

Both of my rifles are Type11 bolt/chambers, I'm using a Beta CHRONY set 10' from the muzzle, sometimes I use my brothers Lab Radar, my powder charges are weighed on a A&D HR-100AZ Lab scale backed up with an old Redding beam scale, so I know my charge weights are correct, my seating depths are just a tic under mag length, my bullets a lightly crimped with a factory crimp die, I know my CHROY is working correctly because I shoot other calibers along with the Grendel and their velocity's are right where they should be!