5 Degree Forcing Cone Results

[aviserated]

I recently cut and cleaned up the factory forcing cone of my 686 from 8 degrees to 5 degrees. I followed Brownells instructions and made sure not to go over .020" of total bullet diameter (in my case .378 was max diameter). I used a new Starline 357 Magnum case to measure rear of forcing cone. Gun now shoots lead bullets more accurately.

Here is a before target @ 25 yards. The two shotgun patterns were shot using SWC bullets.


Here is target after cutting 5 degree cone. @25 yards. This was a test using soft 16/1 (left) vs. hard linotype bullets (right).


Tools


Most accurate bullets (my 686 allways disliked most SWC bullets). Lube is LBT Soft Blue
(L to R) Accurate 36-160Q, RCBS 158 Cowboy, RCBS 140 Cowboy, Saeco 158, RCBS 147 9mm


New 5 degree cone


Factory 8 degree cone. Or is it 9 degree?

 

[Goberto7]

Very interesting improvement that takes into presicion revolver congratulations mate excellent work and very good tool


Enviado desde mi iPhone con Tapatalk

 

[aviserated]

Thanks, I will soon recut my 45 Long Colt Blackhawk to 5 degrees also. According to Brownell's this Blackhwak has the classic 10 or 11 degree cone from the factory.

357 Ruger revolvers have a 5 degree forcing cone from factory.

 

[chief38]

I suspect that JUST the fact that you greatly smoothed it up and took off all the Burrs & roughness the Factory left behind has improved accuracy all on its own. How much the actual angle itself actually helps accuracy is just a bonus. By NOT having a rough FC anymore bullets are not getting scored, deformed and compromised before they even hit the barrel. Good job! The actual ANGLE ITSELF is always a topic of debate for shooters.

 

[aviserated]

The 5 degree 44-45 caliber i just received from Brownells is bad. I just tried cutting the forcing cone on the 45 Blackhawk and this cutter dulled quickly and stopped cutting (soft cutter). This cutter has no manufacturer marks so i am guessing it was made in China. I will return it in exchange for a better one...hopefully they will send me a M. A. Ford brand.

The 38 caliber M. A. Ford cutter i used on my 686 cut very easy and smooth.

 

[aviserated]

The 5 degree 44-45 caliber i just received from Brownells is bad. I just tried cutting the forcing cone on the 45 Blackhawk and this cutter dulled quickly and stopped cutting (soft cutter). This cutter has no manufacturer marks so i am guessing it was made in China. I will return it in exchange for a better one...hopefully they will send me a M. A. Ford brand.

The 38 caliber M. A. Ford cutter i used on my 686 cut very easy and smooth.

The replacement 44-45 caliber 5 degree cutter (part # 080-486-500) i received from Brownells is bad also...it simply will not cut. Brownells stated that these cutters may have missed the heat treating process. I am still trying to resolve this matter with Brownells.

 

[BLUEDOT37]

5 degree FC

On your 686, any idea how much deeper the leade is now than before?

 

[aviserated]

Just by looking and not measuring, i believe 5 degrees extended forcing cone about .060-.080.