6.5 creedmoor primer

[1967spud.com]

do i know you mr hendrix?

 

[howard01233]

What we talking about , spud knows **** all about most things to be honest lol

stay safe every one

So your the god of all 6.5 creedmoor mark , at least I have your number thanks for the game changers, starting to make the rounds. Will be needing some brass for my creedmoor ( large primer) very soon.

 

[1967spud.com]

So your the god of all 6.5 creedmoor mark , at least I have your number thanks for the game changers, starting to make the rounds. Will be needing some brass for my creedmoor ( large primer) very soon.The god of sodall lol but im here when youre ready sir

 

[Laurie]

Has anyone actually tested to see if the British weather is extreme enough to affect a small rifle primer in a Creedmoor load? I've heard numerous things about the cold weather causing problems but the only anecdotal evidence is from some forums where people are shooting in proper extremes of -20°C.

When the SP 308 Win Lapua 'Palma' case was introduced getting on for 10 years ago, I had a look at this in temperatures of 3 to 4 deg C at Diggle in the Pennines in mid winter with a selection of three powders and standard Lapua LP cases as a benchmark. Cartridges were kept in open MTM ammo boxes directly in the path of a cold wind.

Two out of the three showed small MV changes from the SP brass (as expected) and pretty comparable consistency between the types both on the paper and chronograph results.

Viht N140 however saw a large deterioration over LP brass performance and moreover over what one would expect from this 308 Win staple. All three indicators - average MV; MV spread; groups on the paper - were markedly poorer. Reshooting the same range of loads with the same [SP] components on a rather warmer day at ~15-deg C in the spring saw normal performance resume.

Viht N150 by contrast which you wouldn't think would behave any differently showed no downsides at the lower temperatures, and very much to my surprise as ball type powders are traditionally regarded as 'hard to ignite', Hodgdon H414 in a range of charges saw improved performance over LP and even slightly higher MVs.

However, there are ball powders and ball powders. A more recent look at Hodgdon CFE-223 produced excellent LP 308 Win results, but hangfires and a couple of complete misfires in SP brass. Temperature shouldn't have been an issue as it was running around 12 to 13-deg C that day.

More recently, range tests using a 7mm-08 rifle looking for possible Reach compliant alternatives to H4350 last year included the new Viht N555. Results were very good with standard Lapua LP brass (used throughout in these tests), so it was decided to see how well it did a week or two later in Lapua SP Brass (reformed and neck-turned 308 'Palma') which I use in my usual match loads with this rifle with N160. To my surprise, and disappointment, SP brass gave decidedly poorer results - group and MV spreads - than in the LP cases. The ambient temperature was ~10-deg C, so shouldn't have had a major effect.

I've increasingly come to the view that SP ignition is marginal for cartridges whose charges exceed 40gn and that two factors therefore come into play, the primary one being how demanding the powder is on its ignition source. For instance, Viht N150 which is widely used in very heavy charges in 308 Win in F/TR long-range competition shooting works very well indeed in SP brass in all UK conditions, but others obviously either do not like this level of ignition at all, or its use is marginal enough to start to reduce performance at temperatures below a certain level, which I've arbitrarily set at 5-deg C in my own mind.

 

[1967spud.com]

Happy new year Laurie nice read above and surprsiing

 

[howard01233]

When the SP 308 Win Lapua 'Palma' case was introduced getting on for 10 years ago, I had a look at this in temperatures of 3 to 4 deg C at Diggle in the Pennines in mid winter with a selection of three powders and standard Lapua LP cases as a benchmark. Cartridges were kept in open MTM ammo boxes directly in the path of a cold wind.

Two out of the three showed small MV changes from the SP brass (as expected) and pretty comparable consistency between the types both on the paper and chronograph results.

Viht N140 however saw a large deterioration over LP brass performance and moreover over what one would expect from this 308 Win staple. All three indicators - average MV; MV spread; groups on the paper - were markedly poorer. Reshooting the same range of loads with the same [SP] components on a rather warmer day at ~15-deg C in the spring saw normal performance resume.

Viht N150 by contrast which you wouldn't think would behave any differently showed no downsides at the lower temperatures, and very much to my surprise as ball type powders are traditionally regarded as 'hard to ignite', Hodgdon H414 in a range of charges saw improved performance over LP and even slightly higher MVs.

However, there are ball powders and ball powders. A more recent look at Hodgdon CFE-223 produced excellent LP 308 Win results, but hangfires and a couple of complete misfires in SP brass. Temperature shouldn't have been an issue as it was running around 12 to 13-deg C that day.

More recently, range tests using a 7mm-08 rifle looking for possible Reach compliant alternatives to H4350 last year included the new Viht N555. Results were very good with standard Lapua LP brass (used throughout in these tests), so it was decided to see how well it did a week or two later in Lapua SP Brass (reformed and neck-turned 308 'Palma') which I use in my usual match loads with this rifle with N160. To my surprise, and disappointment, SP brass gave decidedly poorer results - group and MV spreads - than in the LP cases. The ambient temperature was ~10-deg C, so shouldn't have had a major effect.

I've increasingly come to the view that SP ignition is marginal for cartridges whose charges exceed 40gn and that two factors therefore come into play, the primary one being how demanding the powder is on its ignition source. For instance, Viht N150 which is widely used in very heavy charges in 308 Win in F/TR long-range competition shooting works very well indeed in SP brass in all UK conditions, but others obviously either do not like this level of ignition at all, or its use is marginal enough to start to reduce performance at temperatures below a certain level, which I've arbitrarily set at 5-deg C in my own mind.

Thank you for such a concise explanation appreciated

 

[Doric]

Please be careful as to which SRP you use in creedmoor. CCI 400s puncture which does the bolt no good at all. I opted for CCI 450 SRP magnum primers which works fine even in a scorching hot Aberdeenshire 15c. down to -18c .

 

[gixer1]

Please be careful as to which SRP you use in creedmoor. CCI 400s puncture which does the bolt no good at all. I opted for CCI 450 SRP magnum primers which works fine even in a scorching hot Aberdeenshire 15c. down to -18c .

I’m also using 450’s in the scorching Aberdoomshire weather!

 

[Gm81]

Please be careful as to which SRP you use in creedmoor. CCI 400s puncture which does the bolt no good at all. I opted for CCI 450 SRP magnum primers which works fine even in a scorching hot Aberdeenshire 15c. down to -18c .

I’m also using 450’s in the scorching Aberdoomshire weather!

This is good to know. I use the same primer and had no issues. But Derbyshire would be long closed in -18. So at least I should be OK