Sooty Necks

[Herb D]

Having swithed from H870 to Retumbo in my 300 RUM Iam now seeing very black carboned necks on my cases -something I've never experienced in 40 years of reloading.
What gives?

 

[royinidaho]

Just 2 comments/questions:

870 and other slow burning ball powders at lower pressures burn quite dirty. At higher pressures this doesn't occur. From what little Retumbo and H1000 I've shot it may be the same with them.

Also I have experienced dirty necks when shooting US 869 at so so pressure.

Just my experience.

 

[Hicks]

Funny, I noticed the same thing this weekend after shooting my 7mm RUM with Retumbo. Never really noticed that before, but then again I've never had a large capacity round like this either.Hicks

 

[crittergitter]

Same story on my new 338/ 300 Ultra that I am breaking in. Sooty necks with Retumbo, a little better with US 869, but not much.

I am curious what kind of performance RoyinIdaho is getting with US869 in the 338 RUM.

 

[royinidaho]

Same story on my new 338/ 300 Ultra that I am breaking in. Sooty necks with Retumbo, a little better with US 869, but not much.

I am curious what kind of performance RoyinIdaho is getting with US869 in the 338 RUM.

101gr US 869/Rem Cases, 300gr SMK/ 2735 FPS /ES+/- 1/ SD = Zip/nadad/nothin'

 

[crittergitter]

I get 2828 with the same charge in the 338/ 300 Ultra in a 34" bbl, but I also get slightly flattened primers and a faint extractor mark. I was suprised by the pressure signs at that charge with the extra case capacity...but 11 fps ES is hard to argue with.

Thanks,

 

[dbhostler]

Herb,
This is usually a result of the bullet exiting the neck too soon after ignition before pressure can expand the neck sufficiently to seal it. You could try greater neck tension to hold the bullet longer, seat the bullet deeper into the case or use a hotter primer. At the very worse, 0000 steel wool will remove it guickly.
db

 

[Herb D]

dbhostler
Your explanation makes sense as do your suggestions. Thanks. Actually the necks clean up with Hoppe's OK.

crittergetter
I'm envious as I don't have the time to work with my new 338-300 until after elk season.

Herb

 

[crittergitter]

Herb

No need for envy. Play time is in short supply here too. I would like to know what you come up with on the 338 - 300 RUM. I'm going to stick with US 869 for now. Retumbo was giving around 70 fps ES.

 

[eshell]

Herb,
This is usually a result of the bullet exiting the neck too soon after ignition before pressure can expand the neck sufficiently to seal it. You could try greater neck tension to hold the bullet longer, seat the bullet deeper into the case or use a hotter primer. . . .

Agreed . . . IMHO, this is right on the money. The pressure has to come up fast enough to obturate the brass.

I reduced the neck fouling of Retumbo in my 6.5-300 Wby by increasing neck tension by .001" and pushing the bullet into the rifling a little.

 

[eshell]

Herb

No need for envy. Play time is in short supply here too. I would like to know what you come up with on the 338 - 300 RUM. I'm going to stick with US 869 for now. Retumbo was giving around 70 fps ES.

FWIW, when I first abandoned H-870 in my 6.5-300Wby and went to Retumbo, I was using Fed 215Ms and got wild ES too. I went to regular Fed 210Ms, adjusted my load back up and ES went to single digits.

I'd like to try US 869 in it - how is fouling compared to H-870 and Retumbo? H-870 was a terrible mess for me, Retumbo isn't too bad.

 

[linksmechanic]

I use retumbo, varget, 4831sc, and blc-2 and all give me carbon on the necks. I'm starting to think it's a hodgdon thing.

 

[crittergitter]

FWIW, when I first abandoned H-870 in my 6.5-300Wby and went to Retumbo, I was using Fed 215Ms and got wild ES too. I went to regular Fed 210Ms, adjusted my load back up and ES went to single digits.

I'd like to try US 869 in it - how is fouling compared to H-870 and Retumbo? H-870 was a terrible mess for me, Retumbo isn't too bad.

Eshell,

I used H870 in my 7mm Rem mag with 168 SMK's for a while and it was a nasty mess. H380 was a nasty mess in my 6mm Rem with 85 grain XLC's. So far, US 869 is cleaner than retumbo and H870 for me. Varget and H4895 are the powders that I use in my 6mm Rem, and 416-06 JDJ. Varget is clean in the 6mm with 55 grain NBT's, but dirty in the 416-06 JDJ with any bullet. H4895 burns quite clean in the .416-06 JDJ Encore pistol with 400 grain Hawk RT's.

Hope this helps.