Steel shot PSI

T

Tom Roberts

Well-known member
Does anyone have a clue what kind of PSI are being generated with modern store bought steel loads in 2 3/4 inch shells. I'm wanting to reload some shells for a classic side by side and was wanting to compare pressures with the factory loads.
 
Hi
This might help but remember that older classic shot guns will not handle steel shot. It is not a pressure issue but a hardness of the steel shot verses the barrel construction.
If you want to hunt with a classic shotgun look into alternative non-toxic shots that are softer then steel shot. Bismuth is one such alternative.
Matt



http://www.randywakeman.com/shotgun_pressures.htm

SAAMI Shotgun Pressure Specifications


[font=Times New Roman, Times, serif]Shotshell Maximum Average Pressure (MAP) in PSI[/font]
[font=Times New Roman, Times, serif]
10 gauge 11,000
12 gauge 11,500 (except 3-1/2 in.)
12 gauge 3 1/2 in.14,000
16 gauge 11,500
20 Gauge 12,000
28 gauge 12,500
.410 Bore 2 1/2 in. 12,500
.410 Bore 3 in. 13,500 [/font]
 
Not sure any over the counter loads but the top pressures on published 2 3/4 reloads are around 11,000-11,500 psi.

How classic of classic is it? Some early guns should probably only have 6,000-8,000 psi.

Tim
 
My gun is a 1925 English made Vickers that has solid steel barrels that have been nitro proofed for 1 1/4oz in 2 3/4inch shell. As best as can be determined/converted to PSI, this gun was pressure tested somewhere in the 13000 PSI ball park. This gun is solidly built for waterfowling and is in really good condition. The chokes on this gun is somewhere in the skeet-imp cyl. range.
 
I've read many threads on the issue of shooting steel in these old guns. Mine is in really good condition with nice thick barrels and was originally proofed for waterfowling. I've heard some say they don't have a problem shooting steel in open choked barrels when shot with modern steel loads with the new shot cups they make today. I plan on loading Ballistic Products ITX nontoxic shot that is supposed to be softer and more compatible with older s x s barrels. What I was concerned about was the pressures some with the loading formulas were generating. With 1 1/8oz shot I'm looking at PSI in the 11000+ area. With 1oz in the 8-9 thousand range. Though most of my duck shots are relatively close over decoys, I'm concerned that an ounce of the ITX isn't sufficient to get the job done. According to my calculations, 1oz of ITX has about 170 pellets. I don't want to shoot my gun apart with the heavier load and greater PSI.
 
I forgot to mention the feet per sec for 1 1/8 oz was around 1300+ whereas 1oz was around 1200. Is 1200 sufficient to drop the ducks? Density of ITX is comparable to lead and bismuth.
 
Tom, remember the Greener '96-1 Rule'. First published in the 1909 edition of The Gun and its Development: Load Gun

1oz of shot 6lb gun
11/8oz of shot 63/4lb gun
11/4oz of shot 71/2lb gun

The gun has to be heavy enough to absorb the recoil. I wish I had known this before destroying a Browning 3"BSS. My older doubles adhere strictly to Greener's rule. Black Cloud makes a 23/4 1oz load that provides a little extra kill power over standard steel and probably has the most protective wad for old barrels on the market. Ballistic Research told me that Kents wad have the least. Something had to give, to gain all that speed. Not an issue on production autos and pumps, but should probably be taken into consideration when shooting older doubles.
 
Tom go to this web site and find the email for Tom Armburst.

He will know the right answers to your questions and he is a reloader big time.

http://www.armbrust.acf2.org/

He has written me back a number of times when I had questions.
 
HI to ya all..

I love older classic doubles and can understand the desire to use one to hunt with. But and that is a big BUT!!! why risk the damage when there are plenty of newer firearms around that are specifically designed to shoot modern loads unless you are willing to load lighter loads, shoot soft shot, and treat the old girl like the gem that she probably is? Just an old buggers rhetorical question to ruminate over and you have probably given that serious thought.

Given the above thought and you decide to take the plunge I wouldn't be timid to use 1 oz loads, over decoys, with a shot that is at least as dense as lead. Funny thing about having learned to shoot waterfowl with a beat up old, single shot, 12 gage, Stevens, lead shot and a poor teenager, you learn to be patient and shoot em close. I used to buy the cheapest 1 or 1 1/8 ounce number 7 1/2 shot, loaded for doves, and under 35 yards kill-em dead as dead can be on a consistent basis. This would be a mixed bag of teal, gadwall, mallards, spoonies, etc. On good days I would average just over one shell per bird if everything was going well (like dummy ducks landing in the decoys committing duckicide).

So I just hope that All American Model 21 isn't going to be used for a paddle........HAHAHAHA!!!! sacrilege!!!!!

As far as shot string velocity, plenty of ducks have been killed with 1100 ft/sec lead loads before the advent of modern 1200-1350 ft/sec loads. You just have to adjust you shooting to the lower velocity loads (lead).

Good luck in your endeavor trying to use the old classic.

Matt
 
Great info. Mike!.....My gun isn't your typical light weight English gun. I see why this gun is rated for 1 1/4oz because it feels fairly heavy and robust.......Thanks.
 
Tom,

Sorry I didn't catch that this was an old English Vickers shot gun...me bad... The granddaughter was bouncing around here like a spring so I didn't see all the post in this thread.

I would try a 1 ounce load. What size shot are you thinking of using?

Matt
 
ITX is not steel shot and shouldn't be loaded the same. I'll second getting in touch with Tom Armbrust, he will steer you in the right direction.
 
Shotgun shells made in the 1920s were measured in lead units of pressure, not PSI. I am not sure what the cross-over would be. Barrels made then did not have the hardness of todays barrels. There was not as much chrome in the metal. They used more nickel back then. The forcing cones and the choke restrictions had a steeper ramp angles. The forcing cone had to seal the gasses quickly or it would circumvent the fiber wads and blow the pattern apart.

Bismuth advertises that it is safe to use in older guns. I might fear putting a nice ring at the end of the barrel where the choke begins.
 
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