doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com John Harper SLE--Birmingham

Are there any other proofmarks on the gun? Anything with tons or bar--like maybe 3 tons or either 850/900 bar? If just 1 oz and 2 3/4", that would indicate a gun proofed between 1925-54. The 1 oz Herters shells currently sold by Cabela's are CIP-approved which means they're OK for British guns like yours. And would probably work well for hunting unless it's really high volume shooting, like doves. Or maybe quail where there's a double digit limit. But if you're shooting a lot, like a box or more, you may find the recoil uncomfortable. RST makes light loads, both 7/8 and 3/4 oz. For games like skeet, and for relatively close shots at birds that don't require a lot of killing, they work great and are very comfortable in terms of recoil.

Under the 1896 Rules of Proof, the 16 bore Service charge was 1 oz. 2 3/4 Dram Eq. = 38 gr. Bulk Nitro powder with the following (+ 10-14% to converted to modern transducer) pressures:
C&H T.S. No. 4 - 7,480;
�Schultze� - 8,250 psi;
�E.C.� - 8,960 psi

Under the 1954 Rules 3 tons/ sq. inch = 8,938 psi by piezo transducer

Shells with those ballistics are the heaviest I'd use; lighter loads will be more comfortable.

Drew, your post pretty much confirms what the former proofmaster said, although he was referring to the 1925 rules and not 1896. He served both before and after the transition from the 1925 rules to the "tons" rules (in 1954), and said that the proof remained the same even though the proofmarks were changed.

Taking one more step, British shell boxes will tell you that standard proof CIP loads are OK in 2 1/2" guns proofed at 3 tons or 850 bar; 2 3/4" shells in guns proofed at 3 1/4 tons or 900 bar. Equating 3 tons to 850 bar and 3 1/4 tons to 900 bar would seem to contradict published transducer pressure equivalences for the "tons" mark, because we know that a gun bearing an 850 bar proof (current CIP standard) equates to a transducer-measured service pressure of 10,730 psi. Something seems out of whack there. However, there are a large number of Webley & Scott post-WWII 700 series guns that were imported to this country with 2 3/4" chambers, 12ga guns marked as 3 1/4 tons. And most buyers likely assumed that since they were made for the US market, that they would handle standard US 2 3/4" ammunition. (I owned a 20ga Model 720 with factory 3" chambers--basically a 702 made for the American market--that was marked 3 1/4 tons. Since it weighed less than 6 pounds, I never had the guts to try it with 3" magnums, and in fact limited factory shells to nothing heavier than an ounce at modest velocity.) Likely not comfortably from a recoil standpoint, if the shot charge were in excess of 1 1/4 oz and/or the velocity in excess of 1300 fps--and especially if both were true. But many have been shot for a long time with lighter and/or slower American loads, and I've not heard of reported disasters as a result. Personally, I too would exercise caution--if for no other reason than excessive recoil. But it is a contradiction in the interpretation of acceptable loads based on proofmarks.

Here's John Brindle in Part 5 of his series in The Double Gun Journal, �Black Powder & Smokeless, Damascus & Steel�; Volume 5, Issue 3, 1994, �Some Modern Fallacies Part 5�, p. 11.
His estimated post-1954 but pre-CIP (finally adopted 1980) pressures by LUP converted to piezo transducer psi.
The Proof House shared with both you (I believe) and Vic Venters that the post-1954 pressures were not greater than those of 1925-1954, and not dissimilar to the 16g post-1896 actual Bulk Smokeless pressures I posted above when 10-14% is added.

.....................Service.....Max. Service.....Proof
12g 2 1/2�.........6,800 psi....8,800 psi.......12,250 psi
12g 2 3/4".........7,800 psi....9,800 psi.......14,050 psi
(CIP 2 3/4" 12g)..10,733 psi...12,328 psi......13,489 psi
16g 2 1/2".........7,300 psi....9,300 psi.......13,150 psi
16g 2 3/4".........7,800 psi....9,800 psi.......14,050 psi

Just to remind us:
3 Tons/sq. inch by LUP (crushers) = 8,938 PSI (pounds/ sq. inch) by transducer using Burrard's formula
3 1/4 Tons = 9,682 psi
3 1/2 Tons = 10,427 psi
3 3/4 Tons = 11,480 psi (The SAAMI maximum for 2 3/4� 12g is 11,500 psi)
4 Tons = 11,917 psi

And I believe the British just enjoy messing with us

BOTTOM LINE: for 2 1/2" chambered 12g limited to 1 1/8 oz., and 16g to 1 oz. shot, pressures should be less than 9000 psi and fps less than 1200.

Ref. the 16 bore. If it's marked 1oz. it should have 2 1/2" chambers. 23/4" chambered 16 bores were marked 1 1/8th. ounce.

You'll not find a bad Harper gun. He mainly made for the Trade; a sort of unsung hero of the gun trade, and seldom sold guns under his own name. Lagopus.....

My records indicated that John Harper, the firm, made just under 1000 guns in their own name over a 75 year period (1902 to 1976). They included single barrel hammer guns, SLEs, BLEs and BLNEs in gauges 12, 16, 20 and .410 Of course, many more were made for the likes of Pape, Churchill, Boss (Robertson), Beesley, Wilkes, Woodward and Dicksons.

In the late 1890s there were 4 Harpers, all in the same family, making guns. John Harper I was a gun action maker. John Harper II started the eponymous firm in 1902; he died in 1937. By then his son John Norman Harper had taken over the firm. It was this last John Harper who became a Birmingham Gun Barrel Proof House Guardian; he died in 1981.

Tim

Thanks! To be on the safe side, I have been shooting 2 1/2" RST 7/8oz. light loads. I just started reloading (new primed hulls) 7/8 oz. 2 1/2" light loads (about 7300psi or so).

The shotgun seems to be in very good shape and shoots well. Its biggest limitation is the shooter.

Thanks again for the replies!

Dr. Drew. RST offers a 16 ga 1 oz load at 1200fps that termed Lite in 2.5 in that I have been using on Texas wild bobs, think these are safe in my W J Jeffery 16 marked 2 1/2 in 1 oz 3 tons per sq in? Only use about 150 shells per season and reload low pressure 3/4 oz or 7/8 oz shells for skeet and SC.

Quail Hunter, got any nice hero shots of your Harper?..I think we'd all like to see a few
chers
franc