How many soldiers were present at the charge down Little Round Top?

Question

The events of July 2, 1863 have been discussed endlessly, from Michael Shaara's The Killer Angels to the film Gettysburg. Since reading the book and seeing the film many times, I can't help but wonder how large each of the opposing forces participating in the defense of Little Round Top truly were.

Wiki provides the number for Union forces on the left flank of the hill (358) from the 20th Maine and 83rd Pennsylvania-- to which we may assume there were heavy losses. But how many soldiers remained from General Law's 4th, 15th and 47th Alabama Regiments and Robertson's 4th and 5th Texas Regiments at the time of the charge down Little Round Top?

Naturally, exact figures will be difficult. Best estimates based on logical or factual evidence appreciated.

Answer 1

The Confederates had 644 troops under the command of Colonel William Oates, compared to the 358 Union soldiers under the command of Colonel Joshua Chamberlain. At the end of the day, Oates reported that only 223 enlisted men and 19 officers responded to roll call, which means he lost nearly half of his men. The 20th Maine under Chamberlain reported having only 200 officers and enlisted men left of their original troops. Chamberlain reported taking 400 prisoners and also claimed that there were 150 dead or wounded Rebels found afterwards, but his numbers appear to have been exagerated.

http://www.historynet.com/battle-of-gettysburg-fighting-at-little-round-top.htm

Answer 2

There were REMNANTS of some 4-5 Confederate regiments at Little Round Top.

Most Confederate regiments started the battle of Gettysburg with 600-800 men. (Their units received "replacements" for casualties, Union units did not.)

Those regiments could have had between 2400-4000 men to start. Take 3200 as the midpoint.

They had also been involved in savage firefights in the Peach Orchard and Devil's Den earlier in the day, which involved roughly 50% casualties on both sides. Perhaps half the survivors made it to Round Top, maybe 600-900 Confederates.

These faced 300-odd Union men under Chamberlain. But Chamberlain's troops were FRESH, fighting their first battle of the day. And they were posted atop a hill. Hence they were more than a mach for two or three times as many men who were "fought out" and demoralized by earlier losses.

Much is made of Chamberlain's running out of ammunition, but the same is almost certainly true of the Confederates. The 200 surviving Union men, charging downhill in a co-ordinated mass, under a unified command, could easily have captured 400 scattered and disorganized Confederates. They almost surely inflicted more than the 100-odd physical casualties they suffered.