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Naphtali
08-20-2008, 11:53 AM
Buffalo Arms Company, and probably others, manufactures lead bullets, unjacketed, with lubrication grooves. How is this done with swaging dies?

georgeld
08-21-2008, 01:05 AM
the may roll them in after swaging. Have you seen some?

Is the groove endless or can you see where the die edge's are??
Like they've used two halve's to squeeze them in.

Southron Sanders
09-14-2008, 11:42 AM
There are several ways to put grease grooves in swaged lead bullets. Although I don't know what swaging process is used in the bullets sold by Buffalo Arms; the old traditional method used in the latter part of the 19th Century was by the use of a two piece die so the grease grooves were impressed when the bullet was swaged.

Of course, when I call it a "two piece die" in actual fact, was technically a "three piece die" as a ram (entering the die from either the bottom or top) was used to compress the lead and form the base of the bullet. The advantage of this system is that a complete bullet is made by one stroke of the press. This is the system used by Northern arsenals and many bullet contractors during The War of Northern Aggression to manufacture Minie Balls for the Yankee army. The Ordnance Department started manufacturing swaged bullets in the early 1850's as swaged lead bullets were considered superior to cast bullets.

A variation of that system used a cylindrical die and ram to form a "smooth sided" Minie Ball and then the swaged piece was actually inserted in a specialized lathe that cut the grease grooves.

Apparantly, the most common system in use today is to also use a cylindrical die and ram to produce a smooth sided lead bullet and then the grease grooves or cannelures are "rolled" into the sides of the bullet at the next phase of the manufacturing process. The disadvantage of this system is that only fairly shallow grease grooves or cannelures can be produced and lead is DISPLACED above and below the grooves or cannelures, increasing the diameter of the lead bullets. This is rectified by then running the bullet thru a "sizing die" to return the bullet to the correct diameter.

With modern bullet production machinery, making lead bullets using these three different manufacturing steps is no problem, as it is done automatically by the machinery and often at the rate of 100 or higher bullets per minute.

Back in the mid-1970's I visited the "surplus auction" that took place at the historic Frankfort Arsenal near Philadelphia when the government was shutting the place down. Needless to say, it was a fascinating trip even though I didn't end up buying anything at the auction.

What I did see was BRAND NEW bullet making and cartridge making machinery made by Waterbury-Farrell STILL IN THE ORIGINAL SHIPPING CRATES that had been lifted up by a crane and then dropped from about 50 feet in the air on to a concrete pad to smash and "de-militerize" the machinery. The purpose of this was to turn brand new, multi-million dollar machinery (purchased at taxpayer expense) into "scrap metal" that could be sold.

Of course, the Waterbury-Farrell machinery I saw at Frankfort that had been scrapped was for making modern, military ammo and consequently much more complicated than machinery used to swage old fashioned, lead bullets.

jimofaz
09-16-2008, 10:54 AM
Buffalo Arms cuts the lubrication grooves on their swaged BPCR bullets on a lathe.
Jim