VV-N133 + 70gr Varmageddon

[notagrendel]

I just got some 70gr Nosler Varmageddons for coyotes. Has anyone messed with VV-N133 with anything around this bullet weight? Is it worth messing with, or is it dependent on higher PPC pressures? Will it cause any issues cycling a rifle +1 on a 18" barrel?

[Old Bob]

I have 25 rounds of 6mm ARC loaded with 25grs of VV-N133 & Nosler 55gr Spitzer bullets in resized 6.5 Grendel brass. I wanted to use the 70gr Varmageddons but they weren't anywhere to be found. I have another 25 loaded with 80gr Sierra SBTs & 22grs of VV-N133. Unfortunately I haven't been able to get to the range to see how either one of them shoot.

notagrendel, where did you find the 70gr Varmageddons?

[notagrendel]

I have 25 rounds of 6mm ARC loaded with 25grs of VV-N133 & Nosler 55gr Spitzer bullets in resized 6.5 Grendel brass. I wanted to use the 70gr Varmageddons but they weren't anywhere to be found. I have another 25 loaded with 80gr Sierra SBTs & 22grs of VV-N133. Unfortunately I haven't been able to get to the range to see how either one of them shoot.

notagrendel, where did you find the 70gr Varmageddons?

I found some factory seconds from SPS and the new ones from Nosler's website.

[Old Bob]

I have 25 rounds of 6mm ARC loaded with 25grs of VV-N133 & Nosler 55gr Spitzer bullets in resized 6.5 Grendel brass. I wanted to use the 70gr Varmageddons but they weren't anywhere to be found. I have another 25 loaded with 80gr Sierra SBTs & 22grs of VV-N133. Unfortunately I haven't been able to get to the range to see how either one of them shoot.

notagrendel, where did you find the 70gr Varmageddons?

I found some factory seconds from SPS and the new ones from Nosler's website.

Thanks notagrendel! SPS was out of the blems but I was able to get a couple of boxes from Nosler. Thanks again...

[notagrendel]

I was able to fire my 70gr Varmageddon test rounds today. I used MP 405 (N133 equivalent) and IMR 4198. Here were my findings:

All strings were 3-shot strings. All strings were under 0.8 MOA.

MP 405: 25.8-27.0gr in 0.4gr increments. Gun did not cycle properly, but occasionally cycled a round through. I did notice in the Hornady PDF had 65gr with N133 data maxing out at 29.1gr, but for whatever reason I played it real safe. I will definitely push it out harder next go-around. 

IMR 4198: 22.3-23.5gr in 0.3gr increments. Up to 22.9gr bolt never attempted to cycle. Past that it attempted, but failed most of the time. Anyone have any data with IMR 4198 and 70gr projectiles and how hard they were able to push it? Lyman 50th in 6 PPC showed max compressed at 23.5gr.

[Old Bob]

notagrendel... do you have any factory ammo & if so, does your rifle cycle with it? It could be your gas system doesn't work well with either of those powders. This is where an adjustable gas block come in handy.

Since I haven't tried IMR4198, & I'm just guessing, it looks like you could have started with a bit more powder. I haven't seen any 6mm ARC loads anywhere with IMR4198 so, like you, I'd have to use the 6PPC as a starting point. Since the case body of the 6mm ARC is 0.027" longer than the 6mm ARC I would probably start at 23grs & work up to 25grs in .2gr increments with the ARC. Not saying you should do that. It's what I would do. I would be keeping an eye out for pressure signs & stop shooting if I see any before reaching 25grs.

I noticed in the Hodgdon manual that for the 6 PPC they only have a one or two grain differences between starting & max loads using IMR4198 with any bullet, 55 to 80grs. That's a pretty narrow load range. Since it's a fast burning powder, I guess it can reach max pressures pretty quick. I used to use IMR4198 shooting cast bullets in my 45-70 Rolling Block. The load range is narrow for that cartridge as well.

I'm not familiar with MP405 powder. Is it Vihtavuori over-run N133 re-labeled as Midwest Powder? I did a little digging & found a site that says to use Vihtavouri data minus 10% for starters with MP405.

Aren't doing load work-ups fun? I think so! :-)

[notagrendel]

notagrendel... do you have any factory ammo & if so, does your rifle cycle with it? It could be your gas system doesn't work well with either of those powders. This is where an adjustable gas block come in handy.

Since I haven't tried IMR4198, & I'm just guessing, it looks like you could have started with a bit more powder. I haven't seen any 6mm ARC loads anywhere with IMR4198 so, like you, I'd have to use the 6PPC as a starting point. Since the case body of the 6mm ARC is 0.027" longer than the 6mm ARC I would probably start at 23grs & work up to 25grs in .2gr increments with the ARC. Not saying you should do that. It's what I would do. I would be keeping an eye out for pressure signs & stop shooting if I see any before reaching 25grs.

I noticed in the Hodgdon manual that for the 6 PPC they only have a one or two grain differences between starting & max loads using IMR4198 with any bullet, 55 to 80grs. That's a pretty narrow load range. Since it's a fast burning powder, I guess it can reach max pressures pretty quick. I used to use IMR4198 shooting cast bullets in my 45-70 Rolling Block. The load range is narrow for that cartridge as well.

I'm not familiar with MP405 powder. Is it Vihtavuori over-run N133 re-labeled as Midwest Powder? I did a little digging & found a site that says to use Vihtavouri data minus 10% for starters with MP405.

Aren't doing load work-ups fun? I think so! :-)

The gas setting is set up with 108gr Match (6 clicks with an SA AGB while running a can). I verified it running a few rounds after the test.

I based my starting points using the Lyman 50th. I found H4198 in Hornady's 10th, but not IMR 4198. After had been running 4198 in 40gr 223 Rem. I should have known that I can push it pretty good past book data, at least I have been able to push it without pressure signs in the past. Also, the 6PPC data in Lyman 50th sat their bullet 0.075" shorter than what I did.

MP 405 is overrun N133. It didn't do well in any of my 223 loads from 40gr to 60gr. In this first round of tests, velocity spreads were pretty bad, but they shrunk as the charge got higher.

I hate being a guinea pig, but someone might as well do it.

[StoneHendge]

Benchmark was the sweet spot for me with 70s and it appears that N133 is around the same speed. Not familiar with 4198, but it appears to be faster than H322 and if so, it's likely too fast.

I'd look forward to seeing your results with it. With Australia under full totalitarian lockdowns and presumably hiding from the Chinese Virus under their beds for years to come, I'm looking for long term replacements for ADI powders and Benchmark is next on the chopping block.

[Lemonaid]

The Hornady gas gun data has Lever listed for the 75 v-max. As I got a keg of Lever for heavy bullets I'll put Lever with light bullets on my list of things to try.

[StoneHendge]

The Hornady gas gun data has Lever listed for the 75 v-max.  As I got a keg of Lever for heavy bullets I'll put Lever with light bullets on my list of things to try.

Save your components. I tried CFE223 with 70s and it's way too slow. Groups were scatter shot and velocity was anemic when pressure started showing. That latter statement comes from a guy who is more than happy with the velocity of 105s with Varget.

I'm guessing Hornady has data for it and 75's because their name is on the canister. They probably get a piece of the action from Hodgdon.

[notagrendel]

Okay guys here's some more data. This time was just single shots and using Hornady 6.5 Grendel virgin formed brass instead of the Starline that I normally used. I have found Hornady brass to produce 15-20 fps more velocity than Starline, but I have found Starline to hold pressures better than Hornady in terms of brass head holding up (rabbit trail over lol).

This is in my 18" Proof Research barrel w/ rifle +1 gas system, custom 6mm silencer and SA gas block tuned for 108gr Hornady 108gr Match ammo. 70gr Varmageddon is seated at 2.150" (0.050" jump).

IMR 4198: spread was around 1" ish.
24.3 -  2934 fps Did not lock bolt back, but ejected case.
24.6 -  2949 fps Did not lock bolt back, but ejected case. Slight ejector swipe.
24.9 -  2987 fps Did not lock bolt back, but ejected case. Slight ejector swipe.
25.2 -  3003 fps Did not lock bolt back, but ejected case. Slight ejector swipe.
25.5 -  3102 fps Did not lock bolt back, but ejected case. Ejector and extractor swipe.
Conclusion: IMR 4198 is too fast of a powder.

MP 405 (N133 equivalent): spread was about 1"
27.5 -  2861 fps Function normally.
27.8 -  2897 fps Function normally.
28.1 -  2917 fps Function normally. Slight ejector smear (anomaly?)
28.4 -  2962 fps Function normally.
28.7 -  2978 fps Function normally.
29.0C -  3013 fps Did not lock bolt back, but ejected case (anomaly?)
Conclusion: Will test top end for groups, maybe take it a step further, but compression might be an issue.

[StoneHendge]

That's pretty close to what I was getting with 70 gr Nosler Ballistic Tip Varmints (interchangeable with the Varmageddons) out of my 18" BHW 243 LBC with Benchmark.  I was able to approach 3050 before I went into bullet conservation mode - that was last summer and I use them in my 6x45.

Remember that your using virgin brass which is essentially base sized. Your case capacity will go up a tad and I've found velocity to increase a bit when using the same charge in fired brass.

Even if you end up around 2900 at around 28.0 gr and have accuracy there (looks like you have a flat spot there, but I've always viewed Satterly as prone to misinterpretation due to normal statistical variances) that bullet is devastating within ethical ranges. I've found accuracy holds to about 300 before dispersion increases while the BTV is good to 450+ before it gets wonky. I do 2960 out of my 24" BHW 6x45 and it is an extremely fast barrel based on published data.

With the bolt not locking back, did you stack the ladder in one mag? You may have had enough pressure to cycle but not lock through the ladder and didn't notice it until the end.

I'm definitely looking forward to seeing your accuracy results.

[notagrendel]

With the bolt not locking back, did you stack the ladder in one mag? You may have had enough pressure to cycle but not lock through the ladder and didn't notice it until the end.

I loaded the mag one round, fired, and checked for bolt lock.

I am anticipating some great accuracy since the test loads were with factory seconds with a rather crappy choice for a seating stem.

[notagrendel]

Okay guys, I am finally getting around to posting the last results of this experiment!

Using the same gun that I have above here is the data:

70gr Nosler Varmageddon
COAL: 2.150 (0.050" jump)
Case HS: 1.181" (B 350 Hornady comparitor)
Brass: Hornady 6.5 Grendel converted. Virgin.
Primer: CCI 450
Powder: MP-405 (N133 O.R.)

Charge   Velocity   ES   100 yd. group
  28.4       2973     43     0.87"
  28.6       2983     22     0.55"
  28.8       3019     51     0.57"

Row in purple is the load I chose for varmint hunting because of the lower ES. Needless to say, I am happy with the experiment. Unfortunately, my friend didn't know how to navigate the MagneetoSpeed chronograph so I just made it simple by using ES.