*Experiment* pushing the 153 a-tip to its limits 6.5cm

[BoltActionBrotherhood]

Hey fellas, just wanted to share my results from some testing I will be doing to push the 6.5 creedmoor to its ballistic limits. This is simply a test and I do not advise you try this for yourselves. I have spent a few years trying to find an optimal load for shooting long range with my 6.5cm. I was hindered by the fact my bolt needed to be bushed before it would allow me to push the cartridge to its limits. well this week I received my new bushed bolt and today I performed a few pressure tests to see how fast I can’t get these 153 atips moving.
I was a bit shocked I reached speeds of nearly 3000 fps.
I tested both RL16 and Rl26. I have tested both powders in the past and landed on Rl16 because of how stable and consistent it was. I felt like I was unable to find a proper node with Rl26. I will continue to test and get some groups in with both powders and will update this thread.
my assumption is, I will want to continue to using Rl16, as it had provided me very consistent groups and speed. (My normal load gets me 2800 FPS with single digit sds. I did tests today in both lapua and Norma brass, I was surprised to find that the Norma brass started showing signs of pressure much sooner that lapua.
I got all the way up to 2990 FPS with lapua with out much visible signs of pressure, and zero heavy bolt lift, (I noticed only very minimal ejector marks starting to form
On the top end load(. Where as the norma I took it up to 2960 and got heavy bolt lift and visible pressure signs, and decided not to fire the last round at 48.0
I will start with the lapua and RL26 because that is the Data I have on my phone currently, and was most impressive and what I will probably continue the majority of this testing with.

Lapua SRP brass
Coal 2.930
Cci 450 mag primers
Case length 1.920
.000 headspace
26inch barrel 1:75 twist
Rifle- Upr10 bolt action
RL26 46.0-48.7 (.003 increments) Satterlee 10 rd load test.
groups to follow in a week or so, but looks like I will be loading at the 2926 node and the 2990/2984 node.

 

[Juggerxxx]

Wow those are some awesome numbers similar to PRC territory. I have played with RL26 and 147eld combo that achieved 3000fps without any pressure signs but these are insane numbers for the 153gr projectile. I’m very surprised at how normal your primers look, still nice and rounded. No ejector marks that I can see on the brass. Please keep us updated on how the primer pockets hold up. I’m guessing the smalls will go the distance.

 

[phlegethon]

That is insanely unsafe. Regardless of what the brass looks like you have to be well beyond design limits for the gun to get velocity like that. Remember that most of us don’t have any way to monitor actual pressure and those with such equient have found that physical signs like ejector swipes happen well after SAAMI pressure limits are exceeded. I wouldn’t do that if I were you and I wouldn’t post it in a public forum.

 

[wpgk58]

I did 200 rounds of 6.5 CM ATip testing with both the 135 and 153 versions, and frankly did not find them to be significantly better than Berger Hybrid or Hornady ELDM. They were slightly better, but not worth the double cost and scarcity. I was pushing the 153 at 2820 fps (SD - 4.3) and 135 at 2890 fps (SD - 2.9) with no signs of pressure and grouping under 1/2 inch. Decided not to continue testing by adjusting jump because I was not going to change.

 

[BoltActionBrotherhood]

That is insanely unsafe. Regardless of what the brass looks like you have to be well beyond design limits for the gun to get velocity like that. Remember that most of us don’t have any way to monitor actual pressure and those with such equient have found that physical signs like ejector swipes happen well after SAAMI pressure limits are exceeded. I wouldn’t do that if I were you and I wouldn’t post it in a public forum.

While your points are valid, I am under the assumptions you have not used RL26 much?
while these velocities are very high, they are not un heard of for the powder. You will see many others are running this powder with this speed with the 147 and 150 gr bullets as a normal load and not running into any issues. I just haven’t seen any reports using the 153s with the powder so I am sharing my results. I have put nearly 5,000 rounds through this gun, and feel very comfortable in knowing when it has reached its limits. I know when this gun is experience pressure issues. With this load, it was not having pressure issues. It’s not just about what the brass looks like, it’s how the gun feels, and the bolt feels.
Thank you for your concern.

 

[b6graham]

That is insanely unsafe. Regardless of what the brass looks like you have to be well beyond design limits for the gun to get velocity like that. Remember that most of us don’t have any way to monitor actual pressure and those with such equient have found that physical signs like ejector swipes happen well after SAAMI pressure limits are exceeded. I wouldn’t do that if I were you and I wouldn’t post it in a public forum.

you dont know that they're unsafe

you're just spouting nonsense.

could be a unicorn barrel and unicorn powder.

 

[BoltActionBrotherhood]

you dont know that they're unsafe

you're just spouting nonsense.

could be a unicorn barrel and unicorn powder.

My barrel does seem a touch faster than some, I actually attribute it to using the Tubbs TMS kit during barrel brake in.
Because once I ran his other bullet kit in my old 6.5 barrel with 4k rounds through it, it sped up quite a bit.

 

[BoltActionBrotherhood]

I did 200 rounds of 6.5 CM ATip testing with both the 135 and 153 versions, and frankly did not find them to be significantly better than Berger Hybrid or Hornady ELDM. They were slightly better, but not worth the double cost and scarcity. I was pushing the 153 at 2820 fps (SD - 4.3) and 135 at 2890 fps (SD - 2.9) with no signs of pressure and grouping under 1/2 inch. Decided not to continue testing by adjusting jump because I was not going to change.

Yeah they are a bit far out there with the prices, I like them just because of how consistent they all are, Two different lots of bullets with have the same exact base to Ogive etc.
I have also been testing all the other 6.5 heavies. I also like the 150k smk, 147, and 144 Berger. I have not been able to get the 156's to shoot good groups though. So far my gun like the 150 the most, and seems to use all the same loads as the 153s.

 

[BoltActionBrotherhood]

I inspected the brass tonight, the lapua primer pockets are still just as tight are good to go.
I will not be using the Norma brass for these top end test, you could really just tell the lapua brass is a better fit for this test. I’ll post some graphs tomorrow.