17HH factory brass weight variance

[PGW Steve]

I'd like to thank the posters for the information I've been reading here over the last while getting set up to load for .17HH and .221 CZs.

I started with some 1680 and 20gr Vmax. Working from starting and up, I was chronographing each shot, and looking for pressure. I was seeing very high jumps, and then a successive shot that was slower, but with more powder. As things got higher, random pierced primers.

Knowing that my procedures were solid, charges were consistent, I checked brass weight. Yikes!!! Some of the cases were 50.5 grains, some were 58. That is a massive variance for a .308 case volume, not to mention the Hornet. I went through the 100 or so empties I had and found exactly 25, clearly an errant lot. I don't know the lot number, but reading old posts here about dished heads and different primer colors, I'm going to check when I get back out to my gear.

I then did some loading with the now same weight brass and had normal pressure, consistent velocity and .4" five shot groups at 3580fps. Hornady factory loads run 3720 out of my 527 Varmint with a BC stock.

I found that 1680 was horrible to work with compared to what I normally am used to, Varget/H4350/H1000....Sticks to the pan, sticks to the funnel. Meters very nice out of a Redding 10X measure however. Any tips on handling 1680??

I also worked up a load for the 221, 40gr Blitzking, 1680, Lapua brass. So far I've yet to shoot a 3 shot group over .5", they typically are .3-.4". I loaded up 20 to do a string of 5 shot groups. Velocity is 3500ish (notes are at my cabin). This rifle is a 527 American, fresh from the factory box.

Thank you for past and future help!

Steve

[montdoug]

Howdy and welcome .
IMO 7.5 grains of weight variance in a Hornet case is a bunch. I'm a bit anal but I formed my own cases using weight segregated WW cases due to all the squawking about the Hornady brass when the round first came out. Dished case heads, tapered primer pockets and what-not, pretty pathetic brass for a new rounds roll-out. A fine round it is too however .
Both I and my 527 .221 Fireball concur that 1680 is the powder of choice for both high velocity and stellar accuracy with 40 grain BlitzKings and 40 grain V-Max's in said .221.
As to the cursed static. Ya might get a fabric softener sheet that is suppose to soften clothes and do away with static when put in the dryer with the clothing. Wipe down the pan and funnel inside and out on occasion while loading with fine ball powders. Wrinkle up the sheet and roll it in your hands real well to get rid of excess dust or even better get a used sheet out of the dryer. That seems to help with the static a fair bit for me. Also, tapping on the pan a bit after pouring the powder in the funnel seems to help as well. Plastic funnels are worse for static then an aluminum one like a Saunders.
Good luck and good shooting.

[Alan in GA]

Wow! That sure might explain the 18 rounds out of 850 (factory ammo) having heavy leakage or totally blown primers my friend experienced in his new CZ 527 on it's first trip to Montana. If he still has those cases I will get and weigh them to find out if they are heavier than the rest. His new CZ Varmint now has leaking primer has erosion in the bolt face. No handloads were used as he invested in the 850 factory loads for the gopher shooting trip we made most years, with the intension of reloading them for the following trips. Didn't happen. Not happy with his first experience with the 17HH. I decided to stay with my tried and true 17AH using Winchester brass, totally happy with it and sold my new CZ527 Varmint 17HH before buying a quantity of brass or taking it to Montana. I think the 17HH was a fantastic idea and introduction of a commercial version of the 17AH, but the first poor ammo and brass was a failure IMO.
BTW, I don't have any problems using handling 1680 and it flows like water. You have static cling from somewhere!!

[dungheap]

I too have used 1680 in this 'n' that for a long time, and never had a sticking issue with it. Others, now and then, but not 1680. Strange!

[Hal]

Alan

If your checking just a few cases, check the case's volume . That will tell you what you need to know.

Hal

[PGW Steve]

Thanks for the replies!

I'm using an aluminum pan and funnel, I'll try the drier sheet trick.

I'll also get a water weight for each case and see what Quick-Load simulates.

I have a case of 250(?) that I haven't cracked open yet, I'm going to fire a few and see what weight those might be. Also a sampling of each individual lot I have left to see if I can determine if they might bear more rotten fruit.

[B23]

I only use Xtreme Hardcore Gear or Satern powder funnels. They aren't cheap and they're caliber specific but they work extremely well and after using them for some time, I'd hate to have to switch back to a plastic funnel.

[Bayou City Boy]

Originally Posted by Hal

Alan

If your checking just a few cases, check the case's volume . That will tell you what you need to know.

Hal

Hal nailed it with his comment above. Case volume has far more to do with load variations than does case weight. Case weight is one indication of possible case volume, but its no exact science by any means. Case volume determines case pressures. If the volume varies significantly, so will pressure.

Greater case volume does not always directly follow in line with lesser case weights, in both large and small brass. In addition, you can have cases with similar weights with significantly different volumes and cases with dissimilar weights that will hold roughly the same volume of powder.

As for the 17HH Hornady brass, it seems that the the Big H marketed something that they didn't fully understand the quality of themselves. However for whatever reason/s some very poor ammunition and brass got out the door and onto dealer shelves as has been documented in previous years, both here and in numerous other places.

Customers learned from experience what Hornady failed to understand or maybe failed to recognize. In a two day period several years ago, two different "technical experts" at Hornady told me two diametrically opposing stories about brass quality. One stated that Hornady recognized that the early 17HH brass quality was an issue and that they were looking into it to solve the issue before any new brass or ammo would be sold. I called them back the next day with a couple of additional questions, and the second one told me the very next day that there was no problem with the 17HH brass, and that all of the problems shooters were experiencing were a result of head space issues with CZ rifles.

And the tooth fairy only carries pesos..........

-BCB

[PGW Steve]

Originally Posted by Bayou City Boy

Hal nailed it with his comment above. Case volume has far more to do with load variations than does case weight. Case weight is one indication of possible case volume, but its no exact science by any means. Case volume determines case pressures. If the volume varies significantly, so will pressure.

Greater case volume does not always directly follow in line with lesser case weights, in both large and small brass. In addition, you can have cases with similar weights with significantly different volumes and cases with dissimilar weights that will hold roughly the same volume of powder.

As for the 17HH Hornady brass, it seems that the the Big H marketed something that they didn't fully understand the quality of themselves. However for whatever reason/s some very poor ammunition and brass got out the door and onto dealer shelves as has been documented in previous years, both here and in numerous other places.

Customers learned from experience what Hornady failed to understand or maybe failed to recognize. In a two day period several years ago, two different "technical experts" at Hornady told me two diametrically opposing stories about brass quality. One stated that Hornady recognized that the early 17HH brass quality was an issue and that they were looking into it to solve the issue before any new brass or ammo would be sold. I called them back the next day with a couple of additional questions, and the second one told me the very next day that there was no problem with the 17HH brass, and that all of the problems shooters were experiencing were a result of head space issues with CZ rifles.

And the tooth fairy only carries pesos..........

-BCB

Yes volume size is the combustion chamber, and that has the effect of changing the pressure. If you have a casing that has consistent external dimensions, for example, it fit in the chamber, and didn't rupture when fired. The external dimensions should be quite consistent based on fired brass. Where does the weight come in? The volume. Since the density of brass is pretty sporty compared to water, there will be a substantial volume difference.

Originally Posted by B23

I only use Xtreme Hardcore Gear or Satern powder funnels. They aren't cheap and they're caliber specific but they work extremely well and after using them for some time, I'd hate to have to switch back to a plastic funnel.

I was using the Satern funnels, I bought a set to cover all the calibers I load. The scale pan is an aluminum Redding one. I thought maybe there was oil on the funnel from manufacturing and wiped it down with methyl alcohol. That wasn't the issue.

[montdoug]

Originally Posted by PGW Steve

Yes volume size is the combustion chamber, and that has the effect of changing the pressure. If you have a casing that has consistent external dimensions, for example, it fit in the chamber, and didn't rupture when fired. The external dimensions should be quite consistent based on fired brass. Where does the weight come in? The volume. Since the density of brass is pretty sporty compared to water, there will be a substantial volume difference.

"BINGO" .
And the smaller the case the more the weight/internal capacity variance affects it.