Standard Deviation Issues

[SmokeTheClay]

For the OP: out of curiosity, how many rounds down range before you give the bore a slight rub down?

say every 5...10...15....or not at all, do you allow for a cool down between shots or do you shoot a string.....cool down.....clean bore resume shooting a string

I am just wondering as how it's done in other parts of the country, I have a nice place to send down range...50 to 600 yrs, but not many folks to shoot with, can't beat the membership fees....$25.00 a year......concrete platforms with canopy for shade...only drawback is summertime heat.....but as stated I'm curious as how others do it

Thank You

[inyocountymark]

Roger that, Thank You

[waveslayer]

How many rounds down the tube? After about 200 my rifles will speed up.

New lot of powder?

What was the temperatures for each range day?

New brass?

Fire formed brass?

At least your SD is single digits, nice!

My wife thinks I only have 3 guns

[SmokeTheClay]

How many rounds down the tube? After about 200 my rifles will speed up.

New lot of powder?

What was the temperatures for each range day?

New brass?

Fire formed brass?

At least your SD is single digits, nice!

My wife thinks I only have 3 guns

New lot of powder? - yep, possibly it

What was the temperatures for each range day? - didnt track it but was warmer the second time. did use hodgon 4350 which supposedly doesnt care about the temp

New brass? - nope. 4th or 5th

Fire formed brass? - nope

At least your SD is single digits, nice! - this is a good thing!

[waveslayer]

I would check your powder lots and also keep a record of temp. Then you can input your temperature stability factor into your ballistics calculator.

On one of my 6.5 Creedmoors I had to reduce my loads by a whole .5 grain because the. We lot of powder was hotter.

Was it H4350 or IMR 4350. There's a difference. H4350 tends to be a slower powder causing more pressure=velocity

H4350 has a temp stability factor of about .29fps per degree change, fyi.

My wife thinks I only have 3 guns

[SmokeTheClay]

Roger that, Thank You