Forcing cone erosion.

Help Support Ruger Forum:

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
Does this look like forcing cone erosion to you?
The gun is a fairly new Blackhawk in .357 with about 200 rounds through it. Mostly .357 with some 9mm.
My .357 load consists of a 158g Ranier hollow point over 10.5g of Blue Dot. This is below SAAMI limits and there are no pressure signs. I did a Bing search and found some folks asking about forcing cone erosion with Blue Dot. It will be a shame if I have to switch to something else. It is a very accurate load. What do you think?

 

Get Wood

Single-Sixer
Joined
Jan 16, 2017
Messages
200
Location
Mid Ohio.
andyo5, I Have NEVER Heard Of Forceing Cone Erosion With Only 200 Rds. If You Are There's Something Else Going On. Just My .02.
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
recumbent said:
Looks ok to me, a little rough but I don'e see erosion.

Do you think that a Lewis Lead Remover (now called Hoppe's Lead Remover) could cause the edge roughness in the photo? I would not have thought so, since the screen is bronze and the cone shaped mandrel it is mounted on is aluminum. But I have used a Lewis Lead Remover on this gun.
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
Hmmm. I am seeing this also on some of my other .357 revolvers, like the Uberti and the GP100 pictured below. I'm wondering whether this might be tool chatter from the manufacturing process.

GP100


Uberti Cattleman
 

recumbent

Buckeye
Joined
Nov 2, 2005
Messages
1,044
Location
South West Indiana
I have 2 GP100, one in 357 mag and 1 in 327 Fed mag. I just checked them both and both of them are smooth. I shoot cast lead and neither one of them leads the barrel.
 
Joined
Aug 3, 2010
Messages
521
Location
Twin Cities, MN
This is forcing cone erosion:

https://photos.app.goo.gl/ygxTJzpa8ZTnEEYH8

This is my 1st GP100 that now has about 15000 rounds through it, mostly with 158 grain bullets and 16.4 grains of Hodgdon's Lil'gun.
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
Well sports fans, I have examined a number of my guns through the magic of photography and have reached the following conclusion:
Guns that have shot this load to any extent show forcing cone erosion. Guns that have shot few or none of this load show no erosion. My S&W model 686 has shot some pretty stout loads with H110 and Alliant 2400 in quantity. Perhaps 30 rounds with this Blue Dot load. It shows only minor erosion, no worse than the Blackhawk which is the main subject of this thread. I think I have an answer.
 

Hondo44

Hawkeye
Joined
Apr 3, 2009
Messages
8,041
Location
People's Republik of California
Yep, you guessed it, it's minor erosion. I haven't ever used enough blue dot to experience it. But I did pick up and old model flat top 357 that was shot a lot, just don't know with what.

But it had erosion worse than this: https://photos.app.goo.gl/ygxTJzpa8ZTnEEYH8

The good news is, the accuracy was still great.

The other good new is I bought it to make a mid frame old model .44 Spl. which is what it is now.

The original 357 barrel I gave to a friend and installed it for him on his old model. He was well aware of the forcing cone erosion but the barrel and labor were free. Some of the erosion was removed establishing a proper barrel/cyl gap. And having fired it, he's perfectly happy with the barrel's performance and doesn't use blue dot, so he's happy.

The bad news is...well there's no bad news.
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
Yeah, Hondo. Looks like I will be moving on to one of my other good loads, such as 15.7g of H110. I get better accuracy with 14.5g of 2400, but that load is hard on guns and unpleasent to shoot. My Uberti actually locked up while I was shooting that load and I had to disassemble it.
I'm also wondering about MP-300 from Alliant. I've never tried it but it is supposed to be for magnum revolver loads.
 

98Redline

Blackhawk
Joined
Dec 9, 2010
Messages
681
Location
PA
H110 , 2400, 4227, N110 are my go to magnum powders, with a heavy preference to H110 and 2400.
Unique for less than full throttle.

I don't think I would have considered Blue Dot in a magnum application. I used it years ago in 9mm and had some odd performance at or near top end loadings. From my understanding when loads get on the hot side it is prone to pressure spikes.

Another powder to say away from in magnum revolvers is LilGun. That powder has a well documented history of throat and forcing cone erosion in magnum powders.
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
98Redline, I got some promising results this afternoon with 7.5g of Unique. I am looking for a higher power load for Silhouette competition and a moderate load for my single actions.
Yes, I have also heard that LilGun can also cause erosion.

Have you ever tried MP300, W231, or BE86 in this caliber?
 

Jimbo357mag

Hawkeye
Joined
Feb 22, 2007
Messages
10,350
Location
So. Florida
andyo5 said:
98Redline, I got some promising results this afternoon with 7.5g of Unique. I am looking for a higher power load for Silhouette competition and a moderate load for my single actions.
Yes, I have also heard that LilGun can also cause erosion.
Its a shame about Blue Dot. It outperforms everything else in my revolvers.
Try Accurate #9 near max and you should have a good powerful load. I hate to hear what you have said about BlueDot as I have shot quite a bit of it and really like it. Now I have some checking to do. :roll:
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
Jimbo357mag said:
andyo5 said:
98Redline, I got some promising results this afternoon with 7.5g of Unique. I am looking for a higher power load for Silhouette competition and a moderate load for my single actions.
Yes, I have also heard that LilGun can also cause erosion.
Its a shame about Blue Dot. It outperforms everything else in my revolvers.
Try Accurate #9 near max and you should have a good powerful load. I hate to hear what you have said about BlueDot as I have shot quite a bit of it and really like it. Now I have some checking to do. :roll:


It may depend on your load. If it is milder than mine, maybe you will be alright. Hopefully you did not use Blue Dot with 125g or lighter bullets. Hodgdon has warned against that it is dangerous to do so.
 

pleadthe2nd

Single-Sixer
Joined
Nov 24, 2016
Messages
213
Location
midwest usa
I have found that 14.5 grains of 2400 behind a 158 gr xtp to be very accurate, in my 6" gp100, you might give it a try with your rainier hp, I repeat very accurate.
 

andyo5

Single-Sixer
Joined
May 9, 2008
Messages
299
Location
Oro Valley, Arizona
pleadthe2nd said:
I have found that 14.5 grains of 2400 behind a 158 gr xtp to be very accurate, in my 6" gp100, you might give it a try with your rainier hp, I repeat very accurate.

You are right. I have tried this load before and it is very accurate. But I dislike shooting it because it is so loud and recoil is stout. My 15.7g H110 load is almost as good but much more pleasent to shoot. The photo shows a reduced load of 15.2g of H110. I settled on 15.7g. I would not go higher than this, in spite of what Hodgdon says.
(You may have to wait a few seconds for the photo to pop up. For some reason it comes up in giant size, even though I reduced it to under 500 kilobytes).


 
Top