I agree with your analysis of the Enfield firing times. That is well documented in many sources. I'm simply questioning Oswald's ability to do it with the Carcano, a cheap scope and mounts. I didn't say it was impossible, I said it was improbable.
Is there any evidence he went to a firing range to sight it in? I've mounted a number of scopes and all required multiple adjustments to get them anywhere near accurate. I lived in Dallas for a year. I know of no ranges in Dallas proper, but I'd guess there are some in various suburban areas. Were any of these checked to determine if Oswald had used any of them?
I'll work backward:
1. Oswald was seen three times at the Sportsdome Gun Range in Grand Prarie, TX (Oct. 26, Nov. 9, and Nov. 17).
2. He stood out for two reasons: He was the only one with an Italian rifle, and he was an outstanding shot. The guy next to him was Garland Slack, and he said that he and Oswald got into a shooting match, and that Oswald was fast, and "centered them all." Sterling Wood recalls Oswald hitting 8 of 10 shots at 100 yards.
Before this, Oswald would take his rifle down to the river where he'd shot bottles he'd toss into the current. He would sit and dry-fire his weapon for hours.
Conclusion: Oswald got plenty of practice.
The Scope:
As already discussed here (multiple times), it is possible to sight UNDER the scope on Oswald's rifle, it was side mounted leaving space to view front and rear sights.
If you are a shooter then look at his two known shots: The first one was low-right, the second one was in the ten ring but also high right. I'm seeing a guy adjust rounds on the fly, not a guy with a $3,000 Zeis scope.
Conclusion: It was an easy shot, Kennedy's head would have looked like a pumpkin through Oswald's cheap scope, assuming he even used his scope.
The Carcano:
The Carcano was a capable weapon, accurate up to 1,000 yards. The barrel had a 1:8 gain twist (higher than the M-16's 1:7), making the round more stable. The bolt was designed for minimal hand movement while transitioning from the trigger, and a practiced shooter I(which Oswald was) would have no problem cycling while maintaining sight picture.
There are plenty of YouTube videos demonstrating this.
And once again we come to the Mannlicher Caracano bullet:
2,700 feet per second - 160 grains, extremely long giving them increased stability when matched with the rifle's 1:8 gain twist. The rounds can penetrate 4 feet of Ponderosa Pine and emerge undamaged.
The 6.5x 52mm round is THE SMOKING GUN pointing to Oswald as the lone shooter. All the damage caused is almost exclusive to the Carcano round; the devastating head shot, the round passing through Kennedy and Connally relatively intact are the bullet's signature. The Carcano round is the white rhino of the ballistics world, not many shooters ever use or see one, and even fewer pathologists have ever dealt with fatal wounds caused by them. In 1963 the Carcano round was as exotic as it would be today in our gun-crazy land.
The lack of understanding the specific 6.5x52mm, 160 grain round, and the Carcano itself, is the root of the problem with JFK Cters who believe there was a second gunman. Had Oswald bought a .306 caliber rifle we'd have something to discuss because they were as common as cigarettes in Texas in 1963 (and even today). The .306 was the round of choice by most marksmen, and had the shooting been a conspiracy where the goal was to frame Oswald they would have either had to have provided him with an M-1, or the second shooter would have had to also had a Carcano, and would have had to be firing from behind the motorcade. This would have been obvious once you understand the 6.5x52mm round, and you'd know there wasn't a second Carcano used.
Bottom Line:
Before you can rule in a conspiracy you have to rule out Oswald, and nobody can. The Carcano makes this impossible.
I will say it again, if you believe there was a conspiracy to kill JFK you won't find it in Dealey Plaza. You might ask who drove Oswald the 13 miles to Grand Prairie, TX. That one has never been nailed down, and while it is debated if Oswald actually went to the shooting range by BOTH sides of the CT issue (CTers allege this was a look-alike, non-CTers don't think the witnesses are reliable and stay away from the subject), if he in fact went to the range someone should figure out the identity of the man he was with at the time.
I doubt the guy knew Oswald was going to kill the President, and I doubt he was anyone special, but until we get an ID it's a question mark.