I believe that more Henry repeaters were used than were Spencers, although the Spencer was first on the battle field, and the coffee grinder model was especially popular. The Spencer, IIRC, only held 7 rounds, loaded through the stock and the hammer had to be manually cocked for each shot. The Henry(the later models)had a tube under the barrel for loading and held about 15 rounds and the hammer was self cocking when the under lever was activated. The Spencer used a more powerful round but the .44 rimfire Henry was more popular with the troops. Both models were late getting into the war, mainly because the Union Quartermaster at that time thought that the troops would use up ammo wastefully and wouldn't approve them until Lincoln personally ordered him to accept the Spencer.
“I believe that more Henry repeaters were used than were Spencers, although the Spencer was first on the battle field, and the coffee grinder model was especially popular. The Spencer, IIRC, only held 7 rounds, loaded through the stock and the hammer had to be manually cocked for each shot. The Henry(the later models)had a tube under the barrel for loading and held about 15 rounds and the hammer was self cocking when the under lever was activated. The Spencer used a more powerful round but the .44 rimfire Henry was more popular with the troops. Both models were late getting into the war, mainly because the Union Quartermaster at that time thought that the troops would use up ammo wastefully and wouldn’t approve them until Lincoln personally ordered him to accept the Spencer.”
The popularity of any “coffee mill” arms remains an open question: US Ordnance records indicate a few Sharps carbines were so modified and field trials may have occurred in 1863-64; after that, no mention can be found. Documented, verified specimens are now so rare that collectors are routinely admonished to suspect fakery.
The Spencer rifle or carbine could not have accommodated the coffee mill device, since any interior spaces of the buttstock that might have been used for the mill had already been filled with the magazine tube and other feed system parts.
The Spencer repeater was in actuality made in larger numbers (114,000; over 107,000 purchased by US government) and used longer (through much of the Indian Wars) than the Henry (14,000 made, 1,900 purchased by US government). It was arguably stronger and less damage-prone: important attributes when we’re talking about field use by troops.
But the Henry rifle captured the popular imagination more fully. It might be called the first “assault rifle”: large capacity (15 rds), less powerful cartridge (44 Henry rimfire Flat: 216 gr bullet, propelling charge 25 gr) than any standard military arm of its day, less even than any fired by the Spencer.
The Henry revolutionized American arms manufacture and use, spawning a long line of descendants: Winchester 1866, 1873, 1876 are but slightly different. The 73 remained in Winchester’s product line until 1919, and replicas of all have been built by overseas gunmakers for decades (original rimfire chamberings have been dropped in favor of somewhat more modern centerfire rounds). Winchester (now a subsidiary of Browning, itself a subsidiary of FNH) recently announced new 73s.
The Henry and descendants - 73 especially - also revolutionized American ammunition production. The 44 Henry Flat and most chamberings for the 76 are no longer made, but every cartridge made for the 73 is still being loaded today. The 22 Short and Long need no introduction: for many decades, Winchester stamped every rimfire round it produced with the letter H in honor of B. Tyler Henry. But the centerfire rounds - 44-40, 38-40, and 32-20 - began life loaded with black powder, made the jump to nitro powder, and have been granted a new lease on life by the sport of cowboy action shooting; all three are uncannily accurate, feed reliably, and perform respectably on any and all targets.