Most earwitnesses heard three shots.
This does not preclude near-simultaneous shots heard by most witnesses as one shot, or the use of a silencer, meaning there were more than three shots.
Most witnesses place the second and third shots as close together.
Secret Service man Kellerman, in the JFK limo, said the the last two shots came in a "flurry" and Gov JBC, before the WC and the HSCA, said the shots arrived in the cab of the limo as if from an "automatic" rifle.
I thought JBC had meant a "semi-automatic," when he testified by the WC, but he repeated his word "automatic" before the HSCA. So JBC says the shots were fired so rapidly he suspected an automatic rifle.
Kellerman, Weitzman and JBC were all knowledgable about weapons and gunfire.