Lengthen Forcing Cones?

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SPEEDY
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Lengthen Forcing Cones?

Post by SPEEDY »

Lengthen Forcing Cones are they worth doing?

I was thinking about buying a reamer lengthen the forcing cones and extend 2 3/4 chambe4s to 3" but I don't know if there 8s any real gain to it.
Does it help any with guns with fixed chokes?

I'm sort of leaning towards getting a reamer and tap to install chokes anyway but I saw this as well and thought maybe it's with doing this too.

Now I'm starting to sort out my workshop a bit I was thinking it would be fun to just pull out all the stops, it cost as much to buy the gear to do it as it does to pay someone to do it one gun so why not go nutts with it.
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Re: Lengthen Forcing Cones?

Post by stokesrj »

I think that lengthened forcing cones aids in recoil slightly but not enough to notice unless you are a competitive shooter firing hundreds of rounds a day. Then the cumulative effect is reduced noticeably. As far as shot patterns go, it can reduce damaged shot keeping some from leaving the patten but more around the edges of the pattern. I haven’t seen it aid pattern density or distribution within the core of the pattern. But I have had only one shotgun with this done to it and seen a few friends do so.
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Re: Lengthen Forcing Cones?

Post by SPEEDY »

It does seem to be only a minor improvement of about 5% or so.
I just wonder if there's truth to the hype, I can understand it in principle but practicable there's no major gain.

I'd probably be better off in investing in choke reamers and taps.
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Re: Lengthen Forcing Cones?

Post by Oscar »

SPEEDY wrote: Sat Apr 06, 2019 9:03 am It does seem to be only a minor improvement of about 5% or so.
I just wonder if there's truth to the hype, I can understand it in principle but practicable there's no major gain.

I'd probably be better off in investing in choke reamers and taps.
Agree with that conclusion. Many of the additional improvements included are in them are worthwhile in competition not so much in the field ( unless you are talking pigeon shooting etc where 100 plus rounds are gone through in the day). However, when you are shooting 150 plus rounds in a day, a few 5% improvements does significantly reduce fatigue levels.

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Re: Lengthen Forcing Cones?

Post by Af300e »

And if the bores are chrome, you’ll be stripping it out where you machine

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Re: Lengthen Forcing Cones?

Post by SPEEDY »

The thing that gets me is read all the great improvements it does, how less deformed pellets means better patterns, but nobody does a before and after pattern.
I've seen improvements in patterns when barrels are back bored, but never with lengthened forcing cones.

That makes me very suspicious.
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Re: Lengthen Forcing Cones?

Post by stokesrj »

I'm in the process of doing a before and after test to see how well it works. My Benelli Ultralight 20 gauge is going to Rob Roberts to get the forcing cone lengthened and then pattern tested with Apex GT20 1 5/8 oz #9 TSS and Winchester Longbeard XR #6 lead shot. I currently have a Rob Roberts Final Strut .560" choke tube on the 24" barrel of this ultralight. With the current set up it is a deadly 40 yard turkey gun and usable at 50 and even 60 yards with the Apex GT20 #9 TSS load but only a 40 yard gun with the Winchester Longbeard load. I'm not expecting much improvement but we will see. It currently puts 260 shot in the 10" circle of the Birchwood Casey Pregame Turkey target using the Apex #9 GT20 load. The #9 TSS out penetrate #4 lead in my ballistic gel tests at 40 yards.

Below is a pic of the current performance which is fantastic for a 20 gauge in my opinion, so we will see if the lengthened facing cones makes the pattern more even, The objective would be to take some of the shot from the center 5' circle where there are far more than needed and move them to the outer edges where there are some gaps. This is the claim that Rob Roberts makes in regards to lengthening the forcing cone. He will also try constrictions either side of the .560 tube I have on it.

The pattern testing done at Rob Roberts is quite unique in that it is automated, using a digital image of the pattern at 40 yards and comparing the 171 locations that a turkey can position it's head in a 15" circle. A perfect score would be 171 meaning that no matter how a turkey could position it's skull within that 15" circle, a pellet would penetrate his brain. This would be a more ideal pattern if the turkey suddenly moves at the shot, which I have had happen. I'll report back the results after lengthening the forcing cone but here is the current performance.
B26E2B4A-D6ED-42F7-AC05-A051FBC54F80.jpeg
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Re: Lengthen Forcing Cones?

Post by SPEEDY »

That will be very interesting to see, I'm not expecting much change but it would be nice to be supprised.
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Re: Lengthen Forcing Cones?

Post by caps »

Af300e wrote: Sat Apr 06, 2019 6:03 pm And if the bores are chrome, you’ll be stripping it out where you machine
Nope, had me shotty's forcing cones and chokes opened up so that I can use steel shot through it about 20 years ago, aside from a wipe down of the barrels externally, it gets its first barrel clean every year at Duck Opening and there is no sign of any rust. The barrels are made from high chromium steel not chrome lined steel.

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Re: Lengthen Forcing Cones?

Post by stokesrj »

I finally got my Benelli ultralight back from Rob Roberts after they had lengthened the forcing cone, installed a slammer button, and pattern testing. I was a little disappointed in the pattern testing. First they used a Federal 1.5 oz #9 TSS load when I specifically requested that the test be done with Apex 1 5/8 oz #9 TSS. Then they didn't give the score for the number of head positions but did give the number of hits in a standard 30" circle, 20", 10" and 3' circle. The number of hits at 40 yards in the 30" circle was an impressive 438 out of 435 pellets in the load for 98.4%. That is pretty good in anyones book. Then there were 400 hits in the 20" circle, 211 in the 10' circle and 40 in a 3" circle and the distribution was very even.

I then shot it at 40 yards with the Apex 1 5/8 oz #9 TSS load today and it did very well. It did move some hits in the center 5" circle out side of the 10" circle as they claimed giving a more even distribution around the 10" circle. It isn't much of a difference unless the turkey moves it head as the shot is fired or I just jerk the trigger.
Benelli UL 20 Pattern.jpg
Benelli UL 20 before forcing cone lengthened.jpeg
Benelli UL 20 after forcing cone lengthen.jpeg
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Re: Lengthen Forcing Cones?

Post by stokesrj »

I think if I were doing this over again with the knowledge I have now, I would skip the forcing cone lengthening and the pattern test, just have them install the slammer button, it is a nice upgrade.
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Re: Lengthen Forcing Cones?

Post by MM »

What is a slammer button?

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Re: Lengthen Forcing Cones?

Post by stokesrj »

It is the bolt release with RR
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Re: Lengthen Forcing Cones?

Post by MM »

Very nice. Is it available for the Ethos?

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