Chương 196: CHAPTER ONE HUNDRED AND NINETY-SIX: FIFTY-SEVEN

The clearance testing finished on the second of April. Four barrels, four blocks, four clearances, run to failure at the same thermal load. Lena ran three of them. Aldric ran the fourth because she had been awake for nineteen hours and Briggs sent her home. The numbers came out as a curve, which was what they had expected, and the curve gave them a clearance that survived a hundred consecutive cycles, which was what they had wanted. The problem was what the hundred cost.

Briggs put it on the bench in front of Marcus on the third of April and did not sit down.

"Hundred cycles at the wide clearance," he said.

"Held all hundred. Didn't bind once."

"So we have it."

"Group at fifty yards is fifty-seven inches." Marcus looked at the sheet.

"Say that in a way I can use."

"At the tight clearance it binds at nineteen cycles and puts every ball inside four inches at fifty yards," Briggs said.

"At the wide clearance it runs all day and I could not hit a barn." He tapped the sheet.

"It's the same fault at both ends. The gap that lets it grow when it's hot is the gap that lets the block sit crooked when it's cold. Wide enough to survive is wide enough to wander."

"And in between?"

"In between is a slope, not a step. Every inch of clearance I give it buys me about six cycles and costs me about four inches of group." Briggs sat down.

"There's no number on that curve where it's both." Reading on Amazon or a pirate site? This novel is from Royal Road. Support the author by reading it there. Marcus read it again.

"What's the fix?"

"There are two and I don't like either." Briggs held up a hand.

"One. Make the block index — a locating pin, a shoulder, something that sets it square regardless of the gap. Then the gap only has to be thermal and the accuracy stops caring about it."

"That sounds correct."

"It is correct. It's also another mechanism inside the mechanism and every one of those is a new way to fail and I do not currently know how to make one that doesn't shear." He put the hand down.

"Nine months. Maybe twelve. Lena thinks eight and she's usually right and I'm still saying nine."

"Two?"

"Two is we accept nineteen cycles." Marcus put the sheet down.

"An engagement is longer than nineteen cycles."

"An engagement is longer than nineteen cycles for one man," Briggs said.

"It is not longer than nineteen cycles for one man with a second barrel."

"You want to issue two."

"I want to issue two and a cooling interval and I want Hollis to build a drill where they swap at fifteen and put the hot one down." Briggs shrugged.

"It's ugly. It's twice the iron, twice the weight in the line, and a man under pressure will not count to fifteen."

"Then why say it?"

"Because it's available in six weeks and the other one is available in nine months," Briggs said, "and I don't know what's coming in nine months. Neither do you. That's the whole of my argument and it isn't an engineering argument, which is why I'm bringing it to you and not deciding it." Marcus turned the sheet over. There was nothing on the back. He turned it again.

"Hollis," he said.

"He'll say issue two. He's a soldier, he'll take the thing that exists."

"He'll say issue two and then he'll build the drill and then in nine months when you have the indexed block he'll have three hundred men trained on a swap they no longer need." Briggs opened his mouth and shut it.

"That's a real cost," he said.

"It's a real cost and it isn't the biggest one." Marcus put the sheet down flat.

"The biggest one is that we'd be issuing a thing we already know is wrong, with a workaround, and telling ourselves it's temporary. We've never done that."

"We have never done that because we have never been in a hurry."

"Are we in a hurry?" Briggs did not answer immediately, which was itself an answer.

"No," he said.

"I want to be. There's nothing on the horizon that says I should be."

"Then nine months," Marcus said.

"Build the indexed block." Briggs gathered the sheets.

"Lena will have it in eight," he said, at the door.

"You said nine."

"I say nine. She has it in eight. That's been the arrangement for two years."