I did find a couple of photos, one captioned "20th Kansas Boys Were Met By Conquered Natives", that shows them armed with Krags, the other photo is their "welcome home" parade in Topeka in Nov 1899. All other photos show them with Trapdoors. The 20th had a good reputation for their actions in the Philippine Insurrection, in part due to having a photographer "imbedded" in the unit, and many of the photos are ACTUAL "combat photos", not staged.
The Regiment's Colonel, Frederick Funston, was quite remarkable. Born in Ohio in 1867, his family moved to Iola KS (about 30 mi. south of Garnett) when he was an infant. He attended KU, worked as a journalist, and spent a year working with the US Dept of Agriculture as a Botanist in Death Valley and Alaska. In 1896, he went to Cuba to fight as a mercenary alongside the Cuban rebels. When Pres. McKinley asked for volunteers regiments from the States in 1898, Funston returned home and presented himself to the Kansas Governor for service. The 20th Kansas Volunteer Infantry was formed, with Funston appointed Colonel. Funston was awarded the Medal of Honor for heroic actions in the Philippines during the insurrection, and when the Regiment returned to the US, Funston remained, and promoted to Brigadier General in the Regular Army. He led the assault that resulted in the capture of self-proclaimed President of the Philippines Emilio Aquinaldo. After P.I. Funston was assigned as Dept Governor of the Philippines for a short time, then Military Governor of the Territory of Hawaii. In 1906, he was Commanding General of the Presidio at San Francisco during the Great Earthquake. His actions during that disaster was credited with saving many lives and property. In 1916, now-Major General Funston was Commanding General of the Southern District of the U.S. during the Mexican Punitive Expedition, and was Pres. Wilson's pick to lead the AEF in Europe in WWI, however Funston dropped dead of a heart attack in Jan 1917 - he was replaced by his immediate subordinate, "Black Jack" Pershing.