Thank you Huvius for your initiative about the Jeffery records: previous 600 NE information came mostly from rare Jeffery ledger pages, some British gun books and the late Cal Pappas book on the subject. His Jeffery chapter seems quite complete, with full word by word transcription of all 600 NE DR and SS recorded in the Jeffery ledger between 1900 to 1929 - yet only one 120 grains service charge Jeffery is recorded.

Regarding that 120 Grains Cordite load which seems to be quite unsettling to some, British proof house rules are very strict and regulated since 1637 but can be confusing. Once a gun has passed proof, in addition to caliber, only maximum service load - which is also the regulation load - are stamped on the barrel flats above each barrel. Annexed a 360 DR barrel flat picture and a simplified explanation of Gun Proof and Gun Marks in England, both under the Rules of 1896 and those of 1904, in practice until after the 1920’s (Gun Digest 1977), whereas “If proofed for nitro loads, they were fired with Cordite proof cartridges generating at least 30% excess stress, and the maximum service load was stamped”.

The misconception that the 120 grains service load is actually the proof charge is again battered by simple mathematics. Following Proof Rules, if 30% charge was added for proof to the lowest 100 Grain service load, what resulting charge should be stamped on the barrels flats ?
In the case of the well-known 577 NE full charge, often also called and stamped 577-100-750, which number correspond to what ?

And Jeffery did use for several years the cartridge description 600 – 120 – 900. The annexed picture is from an original Jeffery catalogue with glued-in 1927 price list. Jeffery was also what is nowadays described as a good marketing man and this Jeffery is the heaviest produced and the first of only 2 with 28 inch barrels. Marketing gimmick to claim more speed and power from that combination ?

To explain in a simple manner the 1900 period Proof Rules, on hand 4 DR barrel flats in picture : that 1902 120 grs 600 under 1896 Rules, a 1913 577 NE (577-100-750) with Birmingham proof after 1904, a 1911 476 NE and a 1912 470 NE, both with London Proof after 1904.

Factually there is a good chance that 100, 110 or even 120 grains cordite does not make any big difference with a 600 under hunting conditions, even head-on charges.

Did Karamanjo Bell not kill 1000 elephants with his 7x57 ? Shooting red deer stags in rut in Europe with the small 5.6x50R barrel of my Bergstützen also cleanly bags game to 150 yards with puny 60 grains bullets. But with today’s rage about Magnum calibers and long distance shooting, is it still true that a small bullet of proper construction in the right place is more effective than a big bullet missing it ? So what is all the fuss about a few extra grains of Cordite ?

What ammunition did Larsen hand over to Schomburgk when he sold this Jeffery ? Which load did the other owners used ? Except for Williamson who wrote about his solid bullets not reaching the brain of an elephant, riveting or braking up due to a post-war change in solid bullet construction (American Rifleman 1956) we know nothing about the powder charge used.

But honestly, who cares ? They all hunted the Big Five in very remote areas, exposed to bush illnesses, ambush by natives, snakes and such plus no helicopter rescue possible. Yet they all survived the many dangerous encounters with interesting stories to tell and trophies to show, somehow it must have worked for all of them in one way or another ?

The book “The history and development of small arms ammunition” is the only one I have seen to date which pictures a probable 120 Grain loaded Jeffery 600 NE cartridge box. Let’s not forget that Jeffery was also a cartridge inventor who chose to release the 600 to the trade, not just a user of the 600. He had certainly direct access to the development department of Kynoch, Eley and others at that time.

Sharing pictures of vintage hunting guns, experiences and adventures of past in oftentimes unexplored and uncharted territory, with the help of one of the guns unmistakably pictured and documented over decades by its different owners was the idea.

Is it safe to assume that none of us were first hand involved with the 600 development around 1900 ? Armchair quarter-backing any story based solely on printed documentation of yore not necessarily reliable feels more like a need to split hairs in 4, or maybe measuring d....

I don't have that need, even when I was itching to try out the Jeffery initially.

To answer another question in the post, Its first trip to the range was with recent manufactured Kynoch 600 NE with soft and solid Woodleigh bullets, and whatever powder charge Kynoch was loading commercially.

Rear trigger first, it was shooting sufficiently well for minute of elephant brain angle.

Woodleigh solids did on average group differently than softs: Solids would have needed more power to come closer. Was it the result of a difference in load between present day factory Kynoch and this Jeffery 120 regulation, or just a day off at the range for me ?

Increasing powder charge, with speed just above 2000 fps by handloading solids did tweak more than an inch in precision and allowed to bring solids and softs in the same place and closer together. Better grouping seemed more recoil than speed sensitive.

Hope to have brought some more clarity in the debate.

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