6.5 Creedmore Reload with N550 at 1.8gr more than recommended max

[GunnyUSMC]

My 6.5 Creedmore is based on an Impact Precision SA with a 26" M24 Bartlein mounted in a Foundation Genesis II stock.

My loads are based on the Berger 140gr VLD with N550 powder. VihtaVouri load data provides a max load of 39gr but that results in a MV of appx 2745. I plan to make an attempt at 1 mile with this system but before doing so, I wanted to get my MV up to around 2850. I did some load development and determined that i can get there with a load of 40.8gr. I shot 50 rounds last weekend to test different bullet seat depths and was pleased with the result. The MVs were very consistent and averaged around 2860. SDs averaged around 7 and all within 4-10 (had only one 10 due to an outlier). Groups at 100yd averaged around .65MOA all within the .37 - .82 range. The cases were barely warm and i did not notice any case or primer deformity. The bulled seat depth i chose to standardize on gave me an SD of 4 and .37MOA group.

Would this have an impact on case life or even barrel life?

Any concerns I should be aware of using a load at 1.8gr over max based on VV load data?

Thanks in advance...

 

[Amay1234]

I have yet to load any rifle ammo with VV powder. But what I've noticed using it for pistol ammo is that their load data is extremely on the safe side. Most published data is though.

 

[canezach]

Will it affect case life? Yes. You are creating significantly more pressure to reach 2860 than 2745. I can't tell you how much that will affect case life, like whether you're cases will only be good for 4 reloads instead of 7, but yes, case life will suffer

Will it affect barrel life? Yes, for largely the same reason. The faster you send the bullet, the faster you'll torch the throat and rifling, but barrel life really shouldn't be your concern. The life difference between 100 fps isn't going to be significant though and barrels are consumables anyway. I've shot out 6.5 Creedmoor barrels in the 2300 round range, give or take a hundredish

I'm not concerned about being over book as long as I'm not seeing pressure signs on my cases, but I would also be concerned about whether the powder is temp stable. A load that is hot in winter will be significantly hotter in summer if the powder isn't stable

 

[GunnyUSMC]

I'm not concerned about being over book as long as I'm not seeing pressure signs on my cases, but I would also be concerned about whether the powder is temp stable. A load that is hot in winter will be significantly hotter in summer if the powder isn't stable

Thanks for the feedback.

What are the key pressure signs you recommend monitoring? In other words, what are the indicators of "too much pressure" on the cases?

I have used brass from Lapua, Peterson, and Alpha Munitions all with small primers. I found that Alpha Munitions brass is noticeably thinner than Lapua and Peterson so will not use the Alpha Munitions brass with hot loads. The loads i mentioned earlier were with Peterson brass. When inspecting the brass, i didnt see anything out of the ordinary but i may not have been looking at the right things.

 

[davere]

What are the key pressure signs you recommend monitoring? In other words, what are the indicators of "too much pressure" on the cases?

Understanding Pressure :: Primal Rights, Inc

Reading pressure is a required skill that all shooters must have. Whether you are shooting factory ammunition or your own handloads, you absolutely must be able to detect and interpret pressure signs on your fired brass.

www.primalrights.com

Depending on your rifle, some cratering of the primer might just be normal - but primer flow, ejector swipes, hard bolt lift, etc, are generally reliable signs that you have issues.

 

[GunnyUSMC]

got it...

not sure what ejector swipes are but will do some research.

Thanks

 

[Dogtown]

Just for a bit more info, here's some predictive data from QL:

I tweaked the N550 parameters to match VV's 39gr load @ 2745 fps, then plugged in 40.8gr to see where you should be: 2874 fps.

Here's what a ladder would give you...

 

[davere]

not sure what ejector swipes are but will do some research.

This is where you read the link I included... LOL

 

[GunnyUSMC]

This is where you read the link I included... LOL

Exactly.... that is the plan

ust for a bit more info, here's some predictive data from QL:

WOW!! that is extremely helpful. What is interesting is that my load testing started at 39 and worked my way up to 41 in .2gr increments which aligns with the process outlined above. I really liked the data at 40.6 and was just 10fps slower (for every .2gr the MV increased by 10fps on average). It was a toss-up for going with 40.6 or 40.8. This helps me realize that 40.6 is where i should be.

Is there a site where i can go to and perform that same analysis?

Thanks again guys... you rock!

 

[Dogtown]

This is the software I used; it's very popular for precision reloading

QuickLoad Ballistic Prediction Software – Neconos.com

www.neconos.com

Keep in mind: it's only predictive. Don't take it as actual ground truth and a replacement for actual load data. Just use it as a predictive guide if you want to see how other powders would perform etc.

 

[GunnyUSMC]

This is the software I used; it's very popular for precision reloading

QuickLoad Ballistic Prediction Software – Neconos.com

www.neconos.com

Keep in mind: it's only predictive. Don't take it as actual ground truth and a replacement for actual load data. Just use it as a predictive guide if you want to see how other powders would perform etc.

Well shoot (pun intended)... I use a MAC and the software is only for Windows...

 

[Dogtown]

Snob