7383 and military brass

[Tom4570]

Got my shippment of 7383 last week from gibrass lot number 48000 which is said to use imr 4831 data minus 15 %. Now my question is if going to use military brass should I also reduce another 10 to 15%? I'm wanting to load this powder in 308 winchester, 243 winchester, and 7/08 remington. Anyone have any suggestion's? Tom

[Rangefinder]

Have a read here and see if this helps you out. After doing so, I cross-checked loads with IMR4064 as they were using against the suggested IMR4831 less 15% and found they were almost smack-on. Under Jim's data he lists a .308 load using LC brass. Maybe take that data and compare against an equivalent book load with 4831-15% and again with 4064 and see where it falls and that should tell you if it's reduced or not. That should give you some base-line to work from.
http://www.castpics.net/LoadData/7383/default.html

[Nobade]

I have used 7383 in all those, and the best thing I can say is to shoot for groups over a chronograph and see what happens. You can't overload a 308 with it, you can come close in a 7mm-08, and really pop the cork in a 243 if the weather is warm. I'd just start at about 90% of available capacity and go up as you shoot to see where it gives the best accuracy and no wired pressure issues. And remember - when it starts to burn clean you have gone too far.

-Nobade

[Jim]

I have used 7383 in all those,..... You can't overload a 308 with it,

With all due respect, I strongly disagree with that. You most certainly can overcharge a .308 with 7383!

.....when it starts to burn clean you have gone too far.

All the research that Wiljen and I have done with 7383 indicates that's the point you're looking for. When it burns clean, that's the time to stop increasing the charge weight. That's also the indicator that it's about to spike.

7383 is very user friendly in tapered cases like .38-55, .375 Winchester, 444 Marlin and .45-70. In tapered case calibers, you can compress it. You try that in a bottleneck caliber and you're going to wind up wearing the rifle.

I've been burnin' this stuff for 11 years and I'm still finding out things about it. It's a very useable powder, but it's nothing to play with if you don't have any experience with it.

[Tom4570]

Well fella's, I do appreciate all the info, I've used surplus powder before but nothing like 7383. I'm still researching. for the time being I will be using the J work projectile in all the cases. It's funny that Jim made mention of the straight wall cartridges in 38/55, 444, and 45/70 as I also have one of each in my locker also. More load work!! any and all info is greatly appreciated. Will post my results.

[Nobade]

I have used 7383 in all those,..... You can't overload a 308 with it,

With all due respect, I strongly disagree with that. You most certainly can overcharge a .308 with 7383!

.....when it starts to burn clean you have gone too far.

All the research that Wiljen and I have done with 7383 indicates that's the point you're looking for. When it burns clean, that's the time to stop increasing the charge weight. That's also the indicator that it's about to spike.

7383 is very user friendly in tapered cases like .38-55, .375 Winchester, 444 Marlin and .45-70. In tapered case calibers, you can compress it. You try that in a bottleneck caliber and you're going to wind up wearing the rifle.

I've been burnin' this stuff for 11 years and I'm still finding out things about it. It's a very useable powder, but it's nothing to play with if you don't have any experience with it.

Well OK, maybe I should say "In my experience you can't overload a 308 with it." - I have tried, and never run into anything resembling pressure problems with 7383 and the 308. But there may be different lots of this powder out there, in different conditions, that may not follow my experiences. This is why I give the cautions and recommend using a chronograph while working up loads. I apologize if I give any incorrect information, and I do urge great caution when using this powder!

-Nobade

[singleshot]

I've been burnin' this stuff for 11 years and I'm still finding out things about it. It's a very useable powder, but it's nothing to play with if you don't have any experience with it. [/B]

So just exactly how did you get experience with it, without playing with it? Serious question BTW, since I have a big box of the stuff and have yet to break it out. Unfortunately, this statement struck me just like, "oh no, you can't get there from here!" :kidding:

[singleshot]

On a similar note, what pressure range is this powder DESIGNED to work in? 35k psi? 45k psi? 55k psi? Higher?

[Tom4570]

:grin:Ok, just because I want to know! which lot number where you using Nobade? and the same question to you Jim which lot number? My research thus far has shown three different lots, all of which are said to burn differently no big surprize there thats the nature of powder lots. Now has any one person experienced two or more of the lots? and which ones are hotter than the others. Experimentation is how I've learned most all of my reloading knowledge and I still have all my body parts, and knock on wood have yet to turn a rifle into scrap.I'd like to keep it that way!!!

[Nobade]

I'll have to get back to you on the lot numbers - they're out in the shop. The first jug I used up is gone so I couldn't tell you, but I have two other batches out there now. So far everything I have tried behaved very similarly.

-Nobade

[Jim]

Nobade, I owe you an apology. After thinking of not what I said, but how I said it, I now realize I could have gone about that in a much nicer way. There's no excuse for being rude.

I apologize, Sir. I beg your forgiveness.

[Nobade]

Nobade, I owe you an apology. After thinking of not what I said, but how I said it, I now realize I could have gone about that in a much nicer way. There's no excuse for being rude.

I apologize, Sir. I beg your forgiveness.

No worries. I certainly realize how easy it is to be misunderstood on the internet! We are all friends here, right?

I just checked the lot numbers of the jugs I have. Curiously enough the current jug I am using has no lot number. But the next six are all RAD 78 L.

I was just thinking about how long I have been using this powder. 11 years sounded like a long time, but I first got some in 2000 so I guess I am at 13 years. My, it doesn't seem like that long but time goes by really fast any more. I sure wish surplus powder was still as available and as cheap as it was back then!

Cheers,
-Nobade

[wiljen]

I have 2 different lot #s with distinctly different burn rates and bulk to them. The maximum loads with all other components the same in 30-06 using 147gr FMJs and WLR primers is almost 4gr different between the two. 7383 is a very useful powder in that it is faster than the other slow burners and cheaper than everything else by a good margin but it does have its limits.

Good rules of thumb -
in cartridges where 4350 or 4831 is appropriate - 7383 will work. 7383 is bulkier than either 4350 or 4831 and generally is going to load at roughly 90% the grain weight and velocity of 4831 due to the bulk. In the big magnums where 4831 is too fast or right on the borderline 7383 is not likely a good choice.

Good loads can usually be found by starting at 85% case fill and working up to 105% slowly. Mild compression sometimes helps, major compression almost always is a bad bad thing. Work your way up watching the bore, when its clean after firing quit. it doesn't get better after that and it can get worse quick.

I have even toyed around with loading 357 max cases with 7383 and while it will work velocities are generally in 38 wadcutter territory.

[Tom4570]

Finally found some time to start working on loads for 308. Used Jims idea and sacrificed a case drilled out primer pocket, seated bullet to depth, and filled to web, result 36.8 grains volume. Reduced 10% 33.1 grains to start. Primers just started to flatten at 37.5 grains and unburnt powder out the wazoo. Now I'm up to 39.0 grains primers flatten a little more and still unburnt powder. Accuracy not to bad at 100 yds. didn't really shoot for that at this point working on pressure didn't crony yet thats the next steps. Temps here low for this time of year 75 - 80 degree when test fire done. Using WLR primers LC 91 brass, think maybe going to mag primers and starting over will help with unburnt powder problem or tread lightly and increase powder a little more?

[sundog]

Comment about the military brass.

Weigh it. Compare it to some different head stamp commercial. A lot of the milsurp brass I've used over the years has actually be about equal or lighter than commercial counter parts. Depends on a lot of factors.

Weigh it.

Some of the heaviest brass I've ever run across was a batch of Frontier 30-06. Good stuff, just a heavy batch.

Weigh and compare. If it is a mixed batch of milsurp, the weight might be all over the place!

The only combination with 7383 that I've done has been absolutely superb; 168 BTHP in 30-06. If memory serves me it was around 48.0-50.0 gr and gave 2495 with SD in single digits and ES in the teens - consistently for 10-shot strings. It is very accurate at 200 yards.

Heed warnings about using this powder. And, no compression.

[wiljen]

I'd keep working up the charge in .1 increments, you are just below where I was in my tests where I got good clean burn.

[Maven]

So just exactly how did you get experience with it, without playing with it? Serious question BTW, since I have a big box of the stuff and have yet to break it out. Unfortunately, this statement struck me just like, "oh no, you can't get there from here!" :kidding:

When IMR 7383 first became available, (It was dirt cheap, btw.), Buckshot, et al., recommended using starting data for IMR 4064 or H 380 in bottlenecked, non-magnum cartridges. You gain experience by starting there and chronographing various load - bullet combinations. That data will suggest whether your lot of 7383 is slower, the same as, or faster than 4064/380. Chrono. results showed my jug was slower than IMR 4064, so I used the same weight bullet (jacketed), but with starting charges of IMR 4350 in both the .30-06 and .243Win. In the former, the result virtually duplicated those I got with 4350. In the latter, not so much: 7383 proved to be a bit faster/hotter than 4350. It is also sensitive to ambient temperature, so be forewarned: hot weather -> higher pressure. While you can use 7383 with CB's, I found it really shines with jacketed bullets in the two previously mentioned cartridges and the 8mm Mau. The problem with the latter is getting enough of it in the case without undue compression to equal the results I get with IMR 4064. Jacketed bullet accuracy is excellent and there is very little unburned powder in either the bbl. or fired cartridge.

[TCLouis]

Wiljen

You mentioned 4 grains difference between two different lot numbers, can you post the lot numbers since that was the gist of the original post?

Does anyone have all three and "relative speed" comparison data?

I did some loading with this powder in 257 and 5.5X257 last summer and promptly lost my load data information.

The good thing when I chronograph loads is that all info is captured in a bound book!

[wiljen]

Wiljen

You mentioned 4 grains difference between two different lot numbers, can you post the lot numbers since that was the gist of the original post?


The two lot #s I have are RAD 78L and LC 85-708 and both came from Hi-Tech if memory serves correctly. The RAD 78L lot is considerably more bulky and a bit faster burning than the LC 85-708.

Having said that with the RAD 78L lot being more bulky, even though its faster I cant match the velocity of the LC lot because I cant fit as much in the case.
so on the 30-06 with 147gr FMJ the RAD 78L tops out at 52gr and 2409 fps average, the LC 85-708 I can get 56gr in (mild compression) and get 2479 fps avg out of that charge.

[9.3X62AL]

I have a couple 8# jugs of this stuff sitting around that I have yet to work with. I'll cop to it......the powder scares me a bit. I don't use enough jacketed bullets in rifles to justify the experimentation currently.

[felix]

Al, I'll buy it from you should you care to sell it. The kids here use it in their 8mm Mausers like it is going out of style (it is, actually). Really. Works at 39-41 grains with 210-180 boolits respectively in that case. A full case full, zero compression, regular primer. ... felix

[MT Gianni]

Al, I had decent luck with cast in the 356 & 358. The 9.3 might be OK with the bore size. Groups are acceptable but not great. [1.75" benched @ 100 yards]

[wiljen]

Al,
I have used 7383 with good success in the 9.3x74r and knowing that capacity of it vs the 62 is barely different I would think it would work well. I would start with a case full to the base of the bullet with no compression and work up to mild compression (maybe 105% case fill). My load with my lot of 7383 (RAD 78L) in the 74r using a 250gr slug is right at 64gr and burns clean using standard CCI primers. Velocity is about 8% below 4831 for the same boolit.

[9.3X62AL]

OK, these notes are promising. Many thanks, gents.

[TCLouis]

Mine came from Bartlett and is Lot 48001

[Tom4570]

Wiljen Still working up in .1 increments up to 39.8 grains still a lot of unburnt powder in the barrel. Primers are flattening now with a little cratering not as flat or as cratered as a 150 grain winchester factory load but close. Bolt is lifting easy and smooth. Accuracy at 100 yards is ok 1" group still have not had a chance to crony. Just a thought you think barrel length may have bearing on the barrel unburnt powder ? I'm working with a 20" tactical barrel on a remington 700.

[wiljen]

I've shot 7383 is some really odd combinations and find that when it gets to a pressure it likes barrel length seems to be a non-factor in clean burn. Shortest barrel so far was a 10" 357 Maximum just goofing off and it still burns clean when it gets to a point it likes. Do understand that the point at which it burns clean will be 1 inch short of a high pressure load so it may be right at the ceiling of what you feel comfortable with when looking at pressure signs.

[felix]

Use case BASE measurements to measure the pressure in YOUR gun, comparing those just fired with those from YOUR factory loads. If expansion is less with your loads, and the primer still expanded a little too much, then the fault is due to the softer primer than that used in the factory load. See if a different primer helps in that arena. The final test next would be to pay attention to the primer hole expansion itself. If the hole is looser for the SAME primer, then the case is too soft for the load. Play games, and pay attention to these details. Use soft cases, soft primers for mouse fart loads ONLY from that point on. The pressure-time curve is just not right using your combination of components in THAT gun. ... felix

[Tom4570]

Well fellas I guess I'm going to have to try a different case with more volume. Last load tested was a well settled full to the top 43.o gr. charge, no bad pressure signs primers look good case head measurements below that of fired factory round by .001 bolt lift good not heavy and still un burnt powder in barrel. Accuracy still 1 inch at 100 yd. Going to have to put on back burner for a while, have to build new man cave outside, taking up to much room inside not enough room for me and wife.

[Nobade]

Looks like you have discovered the same thing I did - can't overload a 308 with 7383, but it shoots pretty well with it just not terribly speedy. Watch out if you go down in bore size though. 243 gets pretty exciting with that powder. My 260 loves it with either cast or J-words, just different amounts.

-Nobade

[ballistim]

I shot a coyote several years ago in my pre 64 model 70 in 30-06 with a load of 7383 and a 150 gr. Game King that groups at a little over 1/2" at a hundred. I hit him in the lungs at 265 yards and aimed a few inches high and it worked out perfect! He went about 10 feet into a fence row and that was it. Made a nice mount, too. I've really had great accuracy in the '06, not so much in .308, 7-08, or 8mm. Nice mild loads though, and I'll save what's left of my 8lbs. for the '06's as it shot well in all three that I've tried it in.

[9.3X62AL]

I'm still looking on, gents. This is sounding better as it continues. Tim, did you use the "default" 7383 formula of "IMR-4831 data minus 15%" to develop loads for the 30-06?

[ballistim]

No, I had someone from a forum recommend using volume for volume charges with IMR 4350, not by weight using Lee formula for Perfect Powder Measure. I'd have to dig up my notes, but it was a lot from Pat's Reloading quite a while ago. I've read Jeff Bartlett mention IMR 4831, but I remember that there were different lots with different burn rates. I liked the fact that I couldn't overfill the cases I tried it in, and always started with at least 80% case capacity. I also had very good results in 7 mm mag as well.

[ballistim]

I'm still looking on, gents. This is sounding better as it continues. Tim, did you use the "default" 7383 formula of "IMR-4831 data minus 15%" to develop loads for the 30-06?

Sorry it took me so long to find my notes on this Al, this information was given to me from a member on the CB-L after I bought four 7lb. jugs of it for $24.00 ea. from Pat's Reloading in 2004. Data was developed by starting with at least 80% case capacity and charges were developed using existing data for IMR4350. Velocity desired for a load was developed by using reloading book data for IMR 4350 and then using the Lee Perfect Powder Measure VMD of .0893 determined by using the conversion formula that an equal volume of IMR 7383 weighed 88% of the same charge of IMR 4350. I verified that the lot of powder I had was representative of this information by substituting IMR 4350 loads I had loaded previously and shot both the IMR 4350 and IMR 7383 side-by-side and was pleased at the similarity of the loads in terms of velocity with no signs of excessive pressure. I hope this information might still be of use to someone developing loads with the lot of powder they have if the burn rate is close enough to what I had. Recommended starting loads can be made by figuring out 80% of maximum case capacity and slowly increasing for best accuracy and desired velocity while checking for signs of pressure. I loaded 7mm-08, 8x57mm, .308, 30-06, 7mm Rem. Mag., and 300 Weatherby Mag. and found all loads to be safe with the best accuracy in the '06, 7mm Rem. Mag., & 300 Weatherby Mag. Hope this helps!

[TCLouis]

ballistim

Do ya mind sharing real load data numbers and boolits/bullets used in the 8X57, 3006, and 7mm Mag?

Any chrono data to go along with the loads?

I have lot # 48001

[ballistim]

I'll PM them if requested, and my biggest reason for not posting them is because of the known fact that there were/are several different lots of this powder with quite different burn rates. I've also read that some of them can have an unexpected spike in pressure signs when increasing loads, so any information I'd give would be for informational purposes only and not recommended loads. I would also try to get as much information on the burn rate from the supplier your powder was purchased from to compare it to what I've used if possible. I hope the data I have is applicable to the current available IMR 7383, but haven't bought any recently and probably should since I think I now have less than 3lbs. on hand of what I've purchased back in 2004. I'd be curious to hear from anyone else who has purchased any recently, specifically from Jeff Bartlett at GI Brass to see how the burn rate of his powder compares. I just have too many irons in the fire to follow up on this at the time, but am curious as to what others have found. Specifically, data and loads using cast bullets would be of interest as I've only ever used it for "J" loads. I DID have a lot of fun burning up this powder at $24.00 per 7lb. jug and having good results, hope you do too... even at $56.00 per 7lb. jug at current prices.

[Tens]

I have 3 jugs of IMR 7383, lot #4800. I've sacrificed a Norma 6.5x55 case, seated a flat based 140 gr Hornady bullet at a OAL of 3.100" with Wolf LR Mag primers and used 43.5 gr of IMR7383 which filed to the base of neck with no compaction (other than tapping while filling). Just got a chronograph and I plan on testing the rounds early one morning this week. I too am concerned about trying it and hope all goes well.

[Buckshot]

.....................Not in the mood to go out into the shop now, but I used 7383 in a few cartridges several years ago. One was the 6.5x55. The 6.5 wasn't it, but on one of the others I got some pressure spiking. If I could walk out there an pull the notebook now, I would. However my load notebooks are set up by cartridge, and I don't recall the others at the moment other then the 6.5 Swede. I didn't even own a 308 then, and now have 2 of'em so that data is of interest to me now. I suspect that besides the 6.5 Swede the probable culprits will be the 8x57, MAYBE the 7x57, and the 30-'06 (although that doesn't ring a bell). Who knows? Heck, may be some 35 Rem or 30-30 stuff! :-)

...............Buckshot

[ballistim]

http://img.tapatalk.com/d/13/08/27/je4ehy9u.jpg

This is what I have and have used.

[ballistim]

PM sent to TCLouis on request.

[Tens]

Buckshot:
I'd be interested in your 6.5x55 experience with IMR 7383, and the lot numbers you used. I loaded 36.5gr and 39.4 gr samples and will start with the lightest, checking for pressure signs and chronograph speeds as I work up to 43.5gr (100% full) on a cool morning.
Tens

[Hamish]

http://www.castpics.net/LoadData/7383/default.html

http://www.castpics.net/LoadData/7383/default.html

http://www.castpics.net/LoadData/7383/Will7383.html

Looking forward to Buckshots data too. (Shouldn't it be in Castpics?)

[wiljen]

Cant put in what hasnt been sent.


http://www.castpics.net/LoadData/7383/default.html

http://www.castpics.net/LoadData/7383/default.html

http://www.castpics.net/LoadData/7383/Will7383.html

Looking forward to Buckshots data too. (Shouldn't it be in Castpics?)

[TCLouis]

So my lot is 48001 from Bartlett.

What are all of the different lot numbers and their relative "speed" fastest to slowest?

Started a separate thread on this so if it gets filled out, it could be a sticky and also be posted at CastPics

[Tens]

All went well this morning. Using a Tweed rifle with a 22" barrel I had the following results with IMR 7383 in Norma 6.5x55 brass using Hornady 130gr with flat base set at an OAL of 3.100". 36.5 gr of IMR 7383 averaged 2214 fps, 39.4 gr averaged 2346 fps, and 43.5 gr averaged 2542 fps with no unburnt powder and no pressure signs using Wolf LR Mag primers. I am pleased.

[ballistim]

All went well this morning. Using a Tweed rifle with a 22" barrel I had the following results with IMR 7383 in Norma 6.5x55 brass using Hornady 130gr with flat base set at an OAL of 3.100". 36.5 gr of IMR 7383 averaged 2214 fps, 39.4 gr averaged 2346 fps, and 43.5 gr averaged 2542 fps with no unburnt powder and no pressure signs using Wolf LR Mag primers. I am pleased.

Glad to hear it went well, have a 6.5x55 myself. Do you know the lot # of your 7383?

[Tens]

The lot number for the IMR 7383 I am using in my test was #48000 which I bought from GIBrass.com

[ballistim]

Thanks for the lot info, am probably going to order some from him and get on the waiting list. I bought 4 jugs of the slow burning WC 872 from him recently.