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Shuz
05-05-2020, 05:30 PM
I have been experiencing some extreme spreads with Reloder 7
That seems to be unusual. I am getting over 100 fps as an extreme spread with only 5 shots . Yesterday I got over 200 fps extreme spread on 1 string of 5. How can one tell if a powder has "gone bad " if it doesn't exhibit the usual warning signs of bad acrid smell or look rusty, etc.

Winger Ed.
05-05-2020, 05:47 PM
We've all read about the 'gone bad' part.

Something I wonder about is since we measure it by weight-
Its made with a certain amount of moisture in the form of solvents that is figured into the load data that I'm sure uses new stuff.

Over time, those solvents evaporate out, even though the old school metal cans.
After a few years, I've thought that even if each little speck has the same energy-

With less solvents, since we weigh a charge, the weight by volume will change.
There will be a few more little granules in a charge weight of old powder than from a new can.

Not enough extra granules to hurt ya,
but maybe enough get a little velocity spread from using powder that has been opened awhile, or a few years old.
Not much, sort of a 'batch to batch' difference, but with the same powder out of the same can.

kevin c
05-20-2020, 12:37 AM
I only load pistol, but, assuming the same components, set up, powder lot, etc., I've personally have had, and have read in other reloading forums about, greater than expected ES from powder clumping and bridging, and especially debris in the measure.

greenjoytj
06-11-2020, 07:47 PM
I have been experiencing some extreme spreads with Reloder 7
That seems to be unusual. I am getting over 100 fps as an extreme spread with only 5 shots . Yesterday I got over 200 fps extreme spread on 1 string of 5. How can one tell if a powder has "gone bad " if it doesn't exhibit the usual warning signs of bad acrid smell or look rusty, etc.

You haven't provided any cartridge details to help guide our replies.
Maybe your RL7 isn't the best powder choice for the cartridge your loading.
Maybe your seeing powder position sensitivity, that is firing with the powder shifted all to the front of the case vs. shifted all to the rear and banked up around the primer flash hole.
Those to different powder position could easily show 100 fps MV difference maybe more depending on the cartridge case size and bullet weight you using.

Larry Gibson
06-12-2020, 09:08 AM
You haven't provided any cartridge details to help guide our replies.
Maybe your RL7 isn't the best powder choice for the cartridge your loading.
Maybe your seeing powder position sensitivity, that is firing with the powder shifted all to the front of the case vs. shifted all to the rear and banked up around the primer flash hole.
Those to different powder position could easily show 100 fps MV difference maybe more depending on the cartridge case size and bullet weight you using.

greenjoyti is correct shuz, you've got to give us a bit more information.

Shuz
06-17-2020, 10:30 AM
OK, sorry I didn't give more info. The gun is a Savage Mdl 16 Weather Warrior in .250 Savage. I am experimenting with powder coated boolits. The load is 15.5g of Reloder 7 and an RCBS 25-100, sized to .258. Primer is Winchester WLR for standard or magnum loads. OAL is 2.341. This load, non powder coated, with this boolit heat treated to Bhn 22, has shot many a 5 shot group at 1 inch or a little more or less. I decided to try this powder coating method to see if I could eliminate the use of gas checks.
I found that eliminating the gas checks enlarged the 5 shot groups and also the velocity extreme spread. Without gas checks I got extreme spreads of 103 and 112. With gas checks the extreme spreads dropped to 75 and 82, and 81 twice. Soooooo, when I first got the extreme spreads of over 100 first time out with the unchecked boolits, I was thinking maybe the powder was suspect. Now it looks like it's a GAs check issue. Comments are appreciated.

Slugster
06-17-2020, 04:35 PM
@Shuz: Are your charges weighed or thrown? Could be bridging in your powder thrower.

swheeler
06-17-2020, 06:31 PM
15.5 grs RL7 is a light load even in the little 250 Savage case with 100gr cast, either put some dacron in the case or switch powders. I would imagine you lost most of your engraving resistance by switching to powder coat making a borderline problem even worse.

Larry Gibson
06-17-2020, 08:03 PM
Shuz

According to CBH #4 that is a starting load for RL7 under a 100 gr cast and is listed with 1691 fps. Using non GC'd PC'd bullets is a bit "over the top for that powder and a non GC'd bullet. Definitely go back to using a GC and try a dacron filler. However, if non GC with a PC bullet is the goal I'd switch to Bullseye at 4 - 6 gr or Unique at 5 - 6 gr.

swheeler
06-18-2020, 09:40 AM
Shuz

According to CBH #4 that is a starting load for RL7 under a 100 gr cast and is listed with 1691 fps. Using non GC'd PC'd bullets is a bit "over the top for that powder and a non GC'd bullet. Definitely go back to using a GC and try a dacron filler. However, if non GC with a PC bullet is the goal I'd switch to Bullseye at 4 - 6 gr or Unique at 5 - 6 gr.

I doubt Shuz is getting that velocity from a bone stock Savage 116 WW, unless he has chrony data to back it up? THAT DATA IS FROM a universal receiver with 24 " barrel, 1-14 twist and would have been chambered to a SAAMI minimum spec chamber. So everything is smaller/less from a std factory rifle, less velocity, less pressure than the 13.6K psi shown in Lyman.

#1-So when you take that water dropped/heat treated 22 BHN casting and bake the powder coat paint on you have annealed back to base alloy BHN what a 9 or 10 bhn. Water drop from the PC oven.
#2 No matter what anyone tells you RL7 doesn't burn effectively at 13K psi, hence the dacron I suggested. It has the secondary effect of helping stop the boolit base from being abraded, I'm thinking the PC does have some affect on stopping this too but don't know for sure.
#3 Since "we" don't know any of the actual numbers/ dimensions/ velocity or pressure of "your" rifle lets take a WAG so you can experiment. Lyman 24 " barrel- you 22" MINUS 50fps, Lyman min spec chamber- you sloppy std, MINUS another 100fps and 2k psi, RCBS boolit instead of the SACEO Lyman used MINUS 50 fps. Now you are shooting PB boolit at 1500 fps and 11k psi pressure and dacron to stop ablating the boolit base, wow completely doable.

If it was me I would at the very least try that bullet PC and water dropped, then some with and without dacron, before I threw in the towel and ran for the box of gas checks. Enjoy ;-)

Shuz
06-18-2020, 10:23 AM
@Shuz: Are your charges weighed or thrown? Could be bridging in your powder thrower.

They are thrown, but in checking various throws, I get 15.4 to 15.6, so 1/10 on either side of 15.5 is "MAS NIX"

swheeler
06-18-2020, 10:31 AM
There's nothing wrong with the powder or the +-charges. It shot fine with heat treated cast bullets and a gas check, you decided to try some of that slick PC paint and plain based, that is whats up.

Shuz
06-18-2020, 10:31 AM
Shuz

According to CBH #4 that is a starting load for RL7 under a 100 gr cast and is listed with 1691 fps. Using non GC'd PC'd bullets is a bit "over the top for that powder and a non GC'd bullet. Definitely go back to using a GC and try a dacron filler. However, if non GC with a PC bullet is the goal I'd switch to Bullseye at 4 - 6 gr or Unique at 5 - 6 gr.

I'm really not set on any particular goal, except getting the smallest groups that I can. The groups I got without powder coating were quite good, but I'd get the occasional flyer that would open a 1" group to 2" or more. I have read that powder coating can somehow "magically eliminate flyers", so I thought I'd try them. I'll try some other powders you suggested and see what goes.

Shuz
06-18-2020, 10:42 AM
I doubt Shuz is getting that velocity from a bone stock Savage 116 WW, unless he has chrony data to back it up? THAT DATA IS FROM a universal receiver with 24 " barrel, 1-14 twist and would have been chambered to a SAAMI minimum spec chamber. So everything is smaller/less from a std factory rifle, less velocity, less pressure than the 13.6K psi shown in Lyman.

#1-So when you take that water dropped/heat treated 22 BHN casting and bake the powder coat paint on you have annealed back to base alloy BHN what a 9 or 10 bhn. Water drop from the PC oven.
#2 No matter what anyone tells you RL7 doesn't burn effectively at 13K psi, hence the dacron I suggested. It has the secondary effect of helping stop the boolit base from being abraded, I'm thinking the PC does have some affect on stopping this too but don't know for sure.
#3 Since "we" don't know any of the actual numbers/ dimensions/ velocity or pressure of "your" rifle lets take a WAG so you can experiment. Lyman 24 " barrel- you 22" MINUS 50fps, Lyman min spec chamber- you sloppy std, MINUS another 100fps and 2k psi, RCBS boolit instead of the SACEO Lyman used MINUS 50 fps. Now you are shooting PB boolit at 1500 fps and 11k psi pressure and dacron to stop ablating the boolit base, wow completely doable.

If it was me I would at the very least try that bullet PC and water dropped, then some with and without dacron, before I threw in the towel and ran for the box of gas checks. Enjoy ;-)

The powder coated boolits I used were quenched after cooking for about 1 hour at 550 deg. They test Saeco 11 after a couplea days.
Dacron scares me because of bbl ringing concerns. I realize many have done it and continue to do it quite successfully, but I don't wanna risk it, cause I can't find another Savage 16 in .250 Savage or another Rem 700 in .250 Savage, and I've gotta stay with a stock rifle for either Production or Hunter class CBA competition. Besides, I load on an old Dillon 450 semi-progressive, and that doesn't really lend itself to dacron stuffing!:bigsmyl2:
Hey guys, thanks for all the suggestions, I really appreciate the ideas.

swheeler
06-18-2020, 10:47 AM
Got ya, carry on. One hour at 550 *F ??, holy smokes are your bullets short, fat and maybe a little deformed.:kidding::guntootsmiley:

edit: Shuz, If you are serious about competing BR with plain based cast bullets you may wish to contact frnkeore, he can answer a lot of the questions I'm sure you have, very knowledgeable gentleman, shoot him a PM

Shuz
06-18-2020, 12:33 PM
Got ya, carry on. One hour at 550 *F ??, holy smokes are your bullets short, fat and maybe a little deformed.:kidding::guntootsmiley:

edit: Shuz, If you are serious about competing BR with plain based cast bullets you may wish to contact frnkeore, he can answer a lot of the questions I'm sure you have, very knowledgeable gentleman, shoot him a PM

Boolits don't appear to be deformed in any way. They still want to roll off the bench when I try to mike them!!
Not interested in plane based BR shooting, I'm happy with Production and Hunter Classes as they are not so prone to spending big bucks to achieve the kind of scores needed. :kidding:

swheeler
06-18-2020, 12:54 PM
550*F seems high to me, bullets would slump I would think, that's right around slush stage for most my alloys. But hey whatever, I thought you were looking to shoot plain based PC boolits, guess I read wrong.

Larry Gibson
06-19-2020, 09:59 AM
I'm really not set on any particular goal, except getting the smallest groups that I can. The groups I got without powder coating were quite good, but I'd get the occasional flyer that would open a 1" group to 2" or more. I have read that powder coating can somehow "magically eliminate flyers", so I thought I'd try them. I'll try some other powders you suggested and see what goes.

All powders have a certain operating pressure where they burn efficiently. Influencing that efficiency of burn is what is called the "rise to pressure". Not to bore anyone with the technical explanation suffice to say the RL7 load you were using with the lubed GC bullet was at the low end of that required pressure. The odd flyers were probably a result of different powder positioning adversely affecting the "rise to pressure". Switching to the non-lubed bullet sans the GC altered and probably lowered the "rise to pressure curve". The end result was the poorer accuracy and much larger ES you experienced. Simply put; the RL7 with those bullets was not consistently igniting and/or burning efficiently.

Assuming your Savage has a 22" barre with a what twist? Also knowing the ES variation you obviously are chronographing the loads so, if you would, advise of the actual measured velocity of the GC'd & lubed bullet vs the non-GC'd & PC'd bullet with the 15.5 gr load of RL7?

I'll not try to convince you of the safety of the dacron filler when used as a filler. Just saying the filler [not to be confused with a "wad" or used as a wad] does promote more efficient and uniform burning of powders such as RL7 when used at less than 80% load density. Given your goal ((post #13) of the smallest groups and that you do not want to use a dacron filler I suggest switching to a fast burning more easily ignited powder that will burn more efficiently. As previously mentioned I most often use Bullseye and Unique for such loads as they do not require nor need a filler.

However, lately, I have been experimenting with Herco. It's a bit slower burning than Unique but ignites easily and burns efficiently and cleanly. It also is a bit bulkier giving slightly better load density. Using normal BR loading techniques of the rifle at the bench I have, so far, not found powder positioning to be a problem. Note there is a thread on this sub-forum running on the use of Herco in CF rifles. They also are reporting excellent results. Might give it a try?

I have read that powder coating can somehow "magically eliminate flyers"

I've read the same thing but have yet to see it.

Shuz
06-20-2020, 01:04 PM
Larry,
The stats on the pc'd non gas checked boolits is as follow:
ES 103 avg vel 1629 sd 38 & Es 112 avg vel 1666 sd 53
With the pc'd and gas checked boolits,the stats were:
ES 75 avg vel 1733 sd 28 & ES 82 avg vel 1782 sd 35
All were shot with 15.6 to 15.8g of Reloder 7 instead of my usual 15.5 because that was what my Dillon measure was throwing the day they were loaded.

Ozark mike
06-20-2020, 01:09 PM
Dont know if it has been mentioned but light neck tension will cause erratic results

Shuz
06-20-2020, 01:15 PM
Larry,
My normal load of 15.5g plusor minus.
Point 1g of Reloder 7 gavv the following stats with normal Non powder coated boolits sized .258 but gas checked and NRA 50/50 LUBE:Es 40 avg vel 1682 sd 17
& ES 49 avg vel 1670 sd 21.
Both these last two 5 shot groups were around an inch. All groups are 5 shots in all stats posted.

Larry Gibson
06-20-2020, 03:08 PM
That seems like an excellent load. I, just this morning, shot a 100 yard 10 shot .8" group with my target M70 308W using a 30 XCB bullet with RL7 powder. It is a very good powder for very accurate cast bullet loads as you point out. As I stated earlier comparing your load with the similar load listed in CBH #4 the use of non-GC'd bullets (designed for GC use) at that velocity puts them "over the top". Just too much velocity for them.

Unfortunately some still believe too many old myths. In this cast that "box stock" rifles can't produce equivalent velocity and pressure that "pressure test" barrels do. Many think that a faster twist barrel of the same cartridge will always give higher pressures....again, just isn't always so. I used to believe those myths too because that's what I had read by all the "renowned" gun writers and "experts". That is, until actual testing proved it "just isn't always so".

As to the comment; "I doubt Shuz is getting that velocity from a bone stock Savage 116 WW, unless he has chrony data to back it up? THAT DATA IS FROM a universal receiver with 24 " barrel, 1-14 twist and would have been chambered to a SAAMI minimum spec chamber. So everything is smaller/less from a std factory rifle, less velocity, less pressure than the 13.6K psi shown in Lyman." We see, from your chronographed results that your "box stock" Savage M16 (22" barrel with a 10" twist?) that you got within 9 fps of the quoted CBH #$ similar load. That's pretty darn close.

Again, if you're just shooting 50 or 100 yards then Bullseye, Unique or Herco might be better powders with your cast bullet sans the GC.

swheeler
06-20-2020, 04:34 PM
Shuz I think it all boils down to post #8. As I said if you don't want to use dacron switch powders;-) I'm still trying to figure out how you're baking for one hour at 550 deg F, personally I think you need to calibrate your thermometer and maybe your chrony too!:bigsmyl2:

Shuz
06-21-2020, 10:45 PM
Shuz I think it all boils down to post #8. As I said if you don't want to use dacron switch powders;-) I'm still trying to figure out how you're baking for one hour at 550 deg F, personally I think you need to calibrate your thermometer and maybe your chrony too!:bigsmyl2:

I'm fairly certain that the temperature was close to 550 because I compared this thermometer with another similar to it and the both gave the same reading. The chrono is an Oehler Model 33 that has served me faithfully for over 35 years.

swheeler
06-22-2020, 01:22 AM
Well I guess if you are shooting 2 MOA and happy with it, carry on. :veryconfu:popcorn:

Shuz
06-22-2020, 04:51 PM
Oh, I do get the occasional 1MOA or better 5 shot group, but it/I am not consistent. I had heard that powder coating could eliminate the occasional flyer that I often get, but so far in rifles, powder coating is just a PITA. Now in the. 44 mag, powder coating is very worthwhile, at least for me.