358 Win. IMR 7383

[Ben]

Today I worked on the last minute " fine tuning " of my Weatherby 358 Win. rifle that Jesse in OR rebored for me.
The rifle now has a 3 groove barrel in it, mirror smooth. A real joy to shoot !

I've got a lot of IMR 7383 on hand. Bought it back when it was $28 for 7 lbs. from Pat's Reloading .

I'm ready to go deer hunting with this load now ( by the way, before putting the rifle away.....I zeroed the rifle to put all 5 in the top of the square you see in the photo )

The Lyman 358318 HP, sized .3592 " and weighing 262 grs. with g/c and lube should be a real killer on deer.

Ben

http://img.photobucket.com/albums/v494/haysb/11122009003.jpg

http://img.photobucket.com/albums/v494/haysb/Lyman%20358318%20HP/PICT0009.jpg

http://img.photobucket.com/albums/v494/haysb/Lyman%20358318%20HP/PICT0004.jpg

http://img.photobucket.com/albums/v494/haysb/Lyman%20358318%20HP/PICT0002.jpg

[Ricochet]

3 groove rifling, that's interesting!

[Linstrum]

That sure is interesting - three-groove rifling!

Interesting boolit, too. Interesting all around, actually. When IMR7383 works, it works darned good. It is a low muzzle flash powder, too, so a larger bore rifle like the .358 won't blind you for a second shot when you are hunting at first and last light of the day.


rl664

[Ben]

IMR 7383 is working as good or better than any powder that I could purchase right now with this particular bullet combination in my 3 different 358 Win. rifles. Anyone with a 358 Win. rifle and some 7383 should give it a try. Although my 40 gr. load is a near 100% case fill, it still gives minor traces of unburned granules. As you can see from the test target above, that by itself isn't a problem to me.

As to the 3 groove rifling, Jesse at :

http://www.35caliber.com/index.html

Jesse has done 2 rifles for me and 2 others for friends of mine. Each and every one is as good or better than a new factory barrel in the accuracy dept. The finish inside the barrel will remind you of the WW II era Springfield 03 - A3 , 2 groove barrels . Mirror smooth

The concept of 3 groove is Jesse's , he seems to be a firm believer in it. The paper targets here on my end of things seems to confirm that he has done his homework.

The height of his lands are .005 ". Not much chance for a cast bullet to " strip " in one of his barrels. I've yet to shoot a .35 caliber cast bullet of any design ( and I have many different .35 cal. molds ) that did not shoot well in my Weatherby Vanguard .358 Win.

When I 1st heard discussions of the concept of reboring, I'll admit that at first I was very skeptical, not anymore.

Ben

[Linstrum]

Hi, Ben, It sure sounds like you have an optimum load combination, what you have sure is a real winner - your photos prove that!

I am interested in reboring work but haven't attempted doing any yet since I am no longer set up for rifling barrels in my machine shop. I have two shot-out Garand barrels that are good candidates for reboring to 8mm-06 and .338-06 calibers since the Garand rifle has proven to be satisfactory in those calibers. The Garand has also been successfully converted to .338 Winchester Magnum.

If the IMR7383 is still showing a few powder mummies (scorched powder granules that look "mummified") that is okay since as soon as IMR7383 starts to burn clean it means that the particular load combination is getting on toward the point of a high pressure excursion that could be dangerous. In the various discussions on IMR7383 (my apologies if you have already read them), one rather nasty characteristic of this powder is that it gives almost no warning of when a maximum load has been reached, this is because it is a triple base high energy powder that has a load pressure rise curve very unlike the single and double base powders we are used to. It is the nitroguanadine used in the powder formulation to reduce muzzle flash and increase its energy content that causes its sudden pressure rise behavior. But when IMR7383 works, it sure works darned good! I use it in my 7.5x54 French MAS 36 rifle with results very much like yours.

Yup, you've got a winner!


rl665

[hicard]

What velocity are you getting with that load of 7383? I have the gun, powder and bullet and I would like to try it.

[Ben]

Linstrum:

Interesting comments on 7383. One should be very cautious with this powder. I've never had a problem with it. Many say that you can substitute IMR 4350 data, I lean more in the direction of IMR - 4064 data for safety reasons.

__________________________________________________ _________

hicard :

I hate to admit it, but I don't own a " chrony ". Beagle has been after me to put that on my list to Santa this yr.

Based on the recoil of the rifle, I'm estimating the 262 gr. bullet to be moving 1,800 - 2,000 fps ? ? It is a pretty potent load. I have no reservations in its use on white-tails. This will be my " go to load " this fall.

My 1st load was 38 grs. of IMR 7383, then I shot 39.0 , then I went to 40 grs.

Shoots accurately, a very few unburned kernels of powder left with the 40 gr. charge, primers look very normal. I'm not certain that I can get any more IMR 7383 in these W-W 358 cases. The load density is very close to 100% ( not compressed, but then again no more room for powder without compression ) with my particular OAL for my particular rifle.

Ben

[Ricochet]

I've said that in certain applications like .22-250 and .30-06 it seemed to be burning like 4350, because the velocities I got with capacity loads of it were similar to the starting loads of 4350 that weighed about the same. (7383 is about 7/8 as dense in bulk as most IMR powders.) And in the original application for the .50 caliber "spotter rifle" on the 106mm recoilless rifle, when 7383 came along to replace 4831 the charge weight relationship was about what you'd expect to see with 4350 and 4831. But pressures jump up suddenly if you compress it, use a very heavy bullet, or greatly increase the shot start pressure. The thing to remember is that the working maximum pressure of the only cartridge 7383 was made for was 38,000 PSI, so the burning rate may turn up steeply above that. In cartridges that will hold a full load of it, I follow the vendor's suggestion of using 4320 & 4064 starting loads as starting points.

[MT Gianni]

Ben, I got good results in my 356 before I sold it with 7383, not so well in the Whelen.

[Ben]

I have not tried IMR 7383 in my 35 Ack Imp. Whelen ( and I may not ).........Certainly works well in the smaller case, 358 Win.

Ben

[Brother_Love]

Wow! Glad I found this thread. I have been shopping at gunshows & gunbroker for a 35 Whelen. I have a J C Higgins model 50 on an FN action that would make a great candidate for re-boring to 35W.

I see that Lyman & RCBS do not have but one mold each available in 358. Are the older ones still around? I could always get a custom mold and I would like to have a HP mold too.

I am going to call JES today about the rebore. The model 50 is 30/06 and I can pick up another '06 anywhere, the new TC venture looks really nice.

Thanks, Malcolm

[Ben]

Malcolm :

Tell Jesse that I sent you. He does some very good work ! !

Ben

[runfiverun]

that comment about the high start pressure certainly is true.
i tried 7383 in the 0-6 with an oversized nosed boolit and my velocities went from a targeted 2k to 2400+ just by upping the start pressure.
the recoil was on the edge too, thought one of the kids slipped in a j-word round on me.
especially when i saw the chrono reading.

[hicard]

Dang it Ben, you forced me to go to my gun shop and order a Ruger All Weather Hawkeye in 358 Win. It is all your fault. Now I will have to try those loads of yours for next years deer season. Picked it up the other day and now the fun begins.

[Ben]

hicard

You won't regret the purchase of the 358 Win.

One of the all time great deer woods cartridges in my opinion.

Ben

[StarMetal]

No flys on a 358 Win but I bet I can buy a Husqvarna complete sporting rifle in 9.3x57 on the 96 action cheaper then you had your barrel rebore work done for?

Joe

[Ben]

Maybe, but I think I'll stick with what I have...........................In the end, I think I'd prefer my Weatherby to a M-96.

[StarMetal]

Check it out:

http://www.allans-armory.com/images/guns/161412SC-001-web.jpg
http://www.allans-armory.com/images/guns/161412SC-002-web.jpg
http://www.allans-armory.com/images/guns/161412SC-003-web.jpg

Not bad,huh?

Joe

[Ben]

Nice ! ! !

Are there anymore like this one ?

What was the price ?

Ben

[StarMetal]

Nice ! ! !

Are there anymore like this one ?

What was the price ?

Ben

That got your attention huh? $375. Don't know how many are left.

Joe

[rugerman1]

Allan's Armory? (http://www.allans-armory.com/aaresult.php?PageId=65)

[looseprojectile]

Is there any chance that you have the Ranch Dog 190 grain boolit?
A friend just got a .358 BLR and has been shooting some of my RD boolits with a mid 40s charge of BL-C. Way fast but accurate. How about a full case of 7383 with this boolit? Not heavy enough? Would like to suggest a load that is a little more within reason.
Funny thing about giving friends boolits for a certain application and having them use them for something not intended. This guy needs a little supervision.

Life is good

[hicard]

Ben, have you tried your bullet and IMR 7383 in 35 Whelen? I just loaded up samples ranging from 40-47 grns to try next time I'm at the range. Just looking for some prior experience so I don't push things too far, if you know what I mean.

[Ben]

looseprojectile :

May or may not work well with the 190 gr. It has been my experience with IMR 7383 that hvy. bullets with near 100% density of the powder charge in the case ( if the case design will tolerate this ) works well.

Luckily for me the 358 Win. with my hvy 262 gr. HP and the powder loaded to near 100 % load density works well.
____________________________________________

hicard:

I have not tried IMR 7383 in the Whelen. Mine is the Ack Imp. Whelen. My 1st thought on the matter is ........NO......., it may not work well. The internal case capacity of my Whelen ACK imp is much greater than my 358 Win.

Getting that " near 100% load density " with IMR 7383 may be difficult or impossible with the Whelen.

Someone else with more experience with 7383 may have different thoughts.

Best,
Ben

[MT Gianni]

I stuck a bolt with 250 gr jacketed and 7383 up to near the base with my Whelen.

[hicard]

What charge were you using MT Gianni?

[MT Gianni]

I am still at work will check tonight. This was 7-8 years ago and it was the starting charge of IMR4350.

[Ben]

Pretty much what I was afraid of in the Whelen. IMR 7383 just doesn't have all that broad of an application. Like someone told me recently, when it works, it works great, But......When it doesn't work, it doesn't work at all !

[Linstrum]

MT Gianni, even though it was a few years back I'm sorry to hear that you stuck the bolt in your Whelen. I hope it didn't cause any damage! Man, IMR7383 is full of all sorts of surprises even when you go strictly by the rules like you did.

For others who haven't read up on it yet, the important things to remember with IMR7383 is that it is a high energy triple base powder, not a conventional single or double base powder with conventional behavior, and it is a darned good idea to start out using IMR4064 data since IMR7383 has a tremendously variable burn rate that seems to vary between IMR4064 and IMR4350 depending on projectile weight and cartridge shape. The most important thing to remember is that what makes IMR7383 so darned treacherous is that it gives no warning that you have reached its safe limits; one load has normal safe pressure with no sign of primer flattening but when you increase it 1/10 of a grain it sticks the bolt and flattens the primer. Work up loads carefully, and stop as soon as it starts to burn clean since you are right at the edge of the danger zone!

Another observation is that the shape of the cartridge plays more of role than with other single and double base powders, the .50 caliber spotter cartridge that IMR7383 was specifically designed for has a squat shape, it is short and fat with approximately the same configuration as a scaled-up 7.62X39 Russian. IMR7383, when used in long slender cartridges like the Whelen, seems to have a greater propensity to have high pressure excursions than in the shorter fatter cartridges like the .358 Win.

IMR7383 is kind of like the old child's nursery rhyme that goes:

"When she was good, she was very, very good; but when she was bad, she was horrid!"


rl689

[felix]

Linstrum, I think it is more about expansion ratio with the amount of powder (energy, and energy type) in the case. Yes, case shape, specifically a steep, sudden shoulder can increase a designated burn speed significantly as proven by me with using various shoulder angles in a 222. That would suggest to me the shorter case as you suggested as compared to the larger would increase the sudden energy potential instead of decreasing it. Therefore, I would suggest that the amount of 7383 in a quasi mid-bore like a 30 caliber should not be greater than 40-45 grains under any circumstance. The idea of looking at grain size after firing is exactly right on. ... felix

[MT Gianni]

What charge were you using MT Gianni?

I can't find my info. I think it is on 3.5" discs and stored. If I were to go by memory it was around 49 gr. It was to the neck of the cartridge. This was in the days we were trying to figure out how this burned. I put the gun in the freezer and the bolt relaxed, no problems with it so far.

[hicard]

Well, I tried IMR 7383 in my 35 Whelen today at the range and it did ok. Shot five loads, 3 shots apiece (15 rounds total) and got one hole (approx) 3/4" at 50 yards using a 250 gr lhpgc bullet(358318 hp/fp). Started with 40 and ended with 45 grs. I did shoot 46 and 47 grs with positive results also, felt a little warm. I feel 45 grs is well enough. Did not have a chronograph but 45 gr loads felt authoritative and were accurate. Pleasant to shoot but they sure are dirty.

[Ben]

hicard :

I've got a 40 degree Ack Imp Whelen. Wonder what charges would work well with 7383 with my 358318HP ?

Ben

[Linstrum]

Hey, hicard, yer computer is ringin'!

Hi, Ben, while you are waiting for hicard to get back with you, I think that hicard's minimum load of 40 grains IMR7383 would be a darned good starting point to start working up from since you would be using the same boolit and the Ackley Improved has a little greater case capacity than the regular Whelen.

From looking at the H.P. White loading data for IMR7383 in the .308 Win and the .30-06 with the same boolit weight being used: The greater the case capacity, the more IMR7383 you can use before getting into trouble.

Since slight variations in bore diameter also play a role in pressure, it is a real good idea not to take maximum or upper end load data straight across from one rifle to another rifle chambered for the same cartridge, so I would stay away from the 46 or 47 grain loadings without first working up to them even though you have the Ackley Improved.


rl695

[Ben]

Hello Linstrum :

Some very solid and conservative ( SAFE ! ) advice to follow in working up loads with IMR 7383 and my Ack Imp Whelen.....Thanks !

Best,
Ben

[hicard]

Sorry it took so long to get back to you. I would think 45 grs would be safe enough to start at as that is what I am really happiest with. 46 and 47 grains seemed a little hot and I am very recoil shy anyway. I really liked the way the 45 gr load felt and shot. The 40-44 grain loads were real pleasures to shoot as far as recoil go.

[Elkins45]

I know this thread is five years old but I thought I would wake it up just to add some data. I chronographed a 235 grain NOE HP over 38.5 grains of 7383 and a CCI 250 magnum primer. Out of my Ruger M77 it averaged 1675 fps and out of my BLR it averaged 1625.

I tested 40.5 grains of IMR 4831 with the same primer and bullet and got right at 1690/1650. For some reason the BLR seems constantly slower than the Ruger.

[Nobade]

Since this thread is getting revived, I'll throw in my 2 cents as well. I have been playing with a 358 (Rem 700) and the NOE #359008, 295gr. boolit with 7383. Just throwing charges gives me velocities similar to Elkins 45, but if I use a 3 foot drop tube I can get enough of it in there to get to 1950 fps. Still no pressure to speak of, and accuracy in the 1.5 MOA range. This is starting to give this little rifle some serious hit!

-Nobade

[Elkins45]

I arrived at the charge weight of 38.5 by using the "Trail Boss method": I filled a case up to the bottom of the bullet and then weighed it. That's what it weighed. The 40.5 charge of 4831 I tried was arrived at by filling the same powder measure with 4831 after I had loaded all of the 7383 rounds and throwing the same volume.

I thought the conventional wisdom was not to compress 7383, or does that mostly apply to cases with higher expansion ratios like 308 and (especially) 243?

A 295 grain bullet at 1950 fps is nothing to sneeze at!

[swheeler]

I arrived at the charge weight of 38.5 by using the "Trail Boss method": I filled a case up to the bottom of the bullet and then weighed it. That's what it weighed. The 40.5 charge of 4831 I tried was arrived at by filling the same powder measure with 4831 after I had loaded all of the 7383 rounds and throwing the same volume.

I thought the conventional wisdom was not to compress 7383, or does that mostly apply to cases with higher expansion ratios like 308 and (especially) 243?

A 295 grain bullet at 1950 fps is nothing to sneeze at!

Elkins I think you have that backwards, the 308 and 243 both have lower expansion ratios than the 358

[Elkins45]

Elkins I think you have that backwards, the 308 and 243 both have lower expansion ratios than the 358

Yeah--I actually looked up expansion ratio and discovered that it isn't exactly what I had inferred it to be. But in practicality I did understand the physics of it OK.

I now understand that expansion ratio is higher in larger bores because more burning volume is created with every inch the bullet travels down a larger diameter bore than a small one. A cylindrical case has a large expansion ratio while a sharply bottlenecked case has a low one.

What I was incorrectly thinking of is the ratio of the case body diameter to the neck diameter. The idea I was thinking of is that for a given case volume/diameter the preferred powder burning rate increases as the neck gets bigger. 243 needs a slower powder than 308, and 358 needs an even faster one because fast burning powders create too much gas too fast for it to squeeze out of the skinny neck of a sharp bottleneck. A big fat case mouth can "let the gas out" and doesn't offer as much resistance to gasses just from having to slam up against a constricting neck/shoulder.

Does this make sense? It's why 257 Weatherby needs really slow powders but 458 Win Mag uses medium ones.