The Applications of different twist rates

[Countryman]

Grateful for that info Racal, thank you.

[Countryman]

I used to use N140 but found better results with other powder, you also get better MV for less pressure with RS52, useful if you find an accurate node in the quicker speeds that would have had you with possible pressure problems with N140 (which is still a good powder for 308)

I tried 175SMK once, still got most of them in a box once I'd pulled the remainder after trying them at 1000 (don't know of any FTR shooters using them in competition)

Interesting! Thanks but I probably still have 6 or 700 of them so I will have to find a load and application. I used these previously quite successfully in the McQueens.

[ovenpaa]

Once upon a time I stuck with one bullet per rifle however as time went by I experimented, some worked well and some less so however I have seldom binned a box, instead I just used them for a different discipline/distance. As an example with my Accuracy International 7,62x51 I use the Lapua 167 for 200-300m McQueen and the Lapua 155 for 1000 with the 170 Lockbase used at 1200. I point the 155 which does make an appreciable difference. The 170 Lockbase also well with the SSG69 P1 I shoot at 600-800.

Some rifles I own just use the single weight/make bullet, as an example I have only ever put the Scenar 123 (Pointed) through my 6,5x47 Accuracy International as it works. Worst one to find something I liked was my 7mm SAUM wildcat and I worked through a variety of bullets before settling on the Berger 180 Hybrid, I still have a half a dozen or so part used boxes of Berger bullets for this rifle however I am sure they will be used at some point :)

[Racalman]

I use two different loads with my .308.

185gn Juggernaut / N550 for 1,000 yards

175gn SMK / N140 for McQueen and anything up to 600 yards.

Both work well.

[Scarface]

Dose barrel length have any effect on the twist rate or is it proportional? "Longer barrel slower twist"

[mullen7]

It's related in the fact that the longer the barrel, the more the bullet will have rotated by the time it has left.
As far as I know twist is not effected by barrel length however this could be a complete load of s***.

[Mattnall]

Dose barrel length have any effect on the twist rate or is it proportional? "Longer barrel slower twist"

No, the twist rate is usually the same for the whole length of the barrel.

It is the length of the individual bullet (if you use the Greenhill formula) that will determine a certain minimum spin and that is immaterial to the length of the barrel as long as you can drive it fast enough as it leave the muzzle to achieve stable flight.

[dromia]

Harry M Pope said that gain twist rifles were "superior in accuracy" to the uniform twist for lead bullet rifles.

[ovenpaa]

Gain twist barrels became fashionable with jacketed bullet shooters a few years ago however I seldom hear of people buying such barrels these days.

[dromia]

Probably not good enough to take advantage of the benefits, unlike Harry M Pope.