Which loads are you considering “light”?
With H322, the listed MAX charge is 21.8gr…which is what I am sticking with as my prefered load
I didn’t use a chrono, but I had fairly clean brass and no pressure signs, so I could have probably gone higher. Won’t try it without a chrono though…
Mostly the 8208.
I was getting a lot of case soot when I was that low. With a Noveske Afghan barrel, 14.5" w/ mid-length gas and a H buffer, I wouldn’t think early extraction was the cause.
With 24.0gr of 8208 behind a 60 gr VMAX at 2.20" and the cases pratically looked new below the necks.
Try with your m&p you will probably be surprised mine shot them fine. I measured the true twist rate to be at 1 in 8.5. So they worked fine.
A lot of people shoot the 77mk in 1 in 9 twist barrels. Bolt guns with longer barrels handle them fine. The added velocity helps with the stability. The slower twist with more velocity give it the additional rpm’s needed for stability in the same way a faster twist with less velocity gives you the added rpm’s.
I see where you measured the twist. If that is accurate you would need a barrel like the rem 700 around 26". You could try to load a few, but with that twist you more than likely will not even be stable at 100. You should not have any problems with the 69. The 69 and below are good to the distance. In wind the bullets will be pushed around.
If you want to use a v max the ones listed are not the best ones to use. They will work, but are not ideal. The one to use is the 53 it has a .290 bc which is better than any of the 22 cal v max. So you can get good velocity with a great bc. The 53 is an overlooked bullet.
V max bullets offer great accuracy. The 55/60 v max are flat base and are great below 300. They will work further out, but flat base bullets are better for shorter range. The boat tails are better at longer distance. It take a boat tail longer to go to sleep.
Op if you want i would trade you some 69 nosler custom competition for your 77’s. I would give you more cc’s for mk’s to make up the price difference. I even have some of the 53 v max bullets i got for Christmas one year. I do not shoot v max bullets at all any more. For lighter bullets i shoot the 52/53 matchkings which are great bullets for slower twist barrels.
I think I remember the article that I read where this myth is refuted.
It was in Handloader Magazine. I’ll try to dig it up and post the quote tonight.
IIRC, at slower velocity, the spin requirement was lower to keep the bullet stable as it pushed throught the air.
What kind of velocities are you guys getting with the h322 and 77s?
I wouldn’t mind loading up some extreme powder up to near max.
We shoot it through so many different Barrel lengths, I can’t remember.
Our buddy chrono’d it against the M262 load and it was 150ps lower than that with a similar POI.
I just load it to right at published max, and it stacks holes and will reach a thousand yards… so 
I’m not messing with it.
Gotcha, hey if it works… Just like the Lyman no 49 shows highest velocities for the same with aa2230… I need to get a chrony
There are quite a few in the no. 49 that are in the 2800 FPS range.
Sierra has 24.0 gr of TAC at 2750 out of a 20" barrel. AA-2520 is listed at 2700 FPS with a 24.2 gr drop.
With reloading componets I find more and more the need to see what is in stock and make a choice out of that.
I have 45 or so 77 gr Noslers left. I’ll have to see about getting some H322.
According to Hodgdon… 
This extreme powder has won more benchrest matches than all other propellants combined. It provides match grade accuracy in small and medium capacity cartridges like the 223 Remington, 6mm PPC and the 7mm TCU. As a fine extruded powder, it flows through powder measures with superb accuracy.
I think they say that about every powder they make…
That one is actually true from talking to folks. For a period, H322 was the benchresters’ powder.
I think they flocked to Vihtavouri since.
Markm the way i explained it may be wrong, but i know and talked to a lot of people who can not get the bullet to stabilize out of 16" 1 in 9 barrels. When the barrel is 20-26 in bolt guns they get excellent results. So my theory may be wrong but it seems that velocity is the key to stability.
Later Im going to put some numbers into the jbm stability calculator, and see where the stability limit is for a 1 in 9 twist. Then see if the velocity is achievable without using a 20" plus barrel. Ill post what i find.
One thing that does not make sense is only a couple manufactures make bolt guns faster than 1 in 9. Another thing that does not make sense to me is AR manufactures using a 1 in 9 barrel.
For sure! I’ll post my article info. Not that the article is necessarily correct… you know? 
You never know if the articles are sufficiently researched, but handloader magazine is generally pretty accurate. The jbm calculators are very nice for questions like this. With the op’s twist rate being closer to 1 in 10, it is doubtful he will have any success. If he wanted them for home defense he would be fine, but past 25-50 yards they will probably be tumbling.
When i do the calculations Im going to use his twist rate along with a 1 in 9 to see the difference.
I stopped my subscription to handloader magazine about a year ago. The articles started to be of less interest to me. Now that i do not get it i miss it. Do you remember what issue it was? I found some of my old ones from right before i canceled the subscription.
Markm the 1 in 9 twist barrel you shoot the 77mk’s out of is it a gas or bolt gun? How many 1 in 9’s do you shoot? What barrel length are they?
The bolt gun is a nominal 1/9 20 inch barrel. We’ve not checked for the exact rate.
The article is on the OVER-stabilization debate, but the author hits on the topic we are discussing.
Here is the quote from the article:
December 2012
Handloader Magazine
“Rifle Bullet Stability”
by John Barsness
Most shooters believe extra muzzle velocity helps stabilize a bullet. Like the myth of overstabilization, this contains a kernel of truth, but in reality extra velocity only helps a tiny amount. There are two conflicting factors in stabilization: the bullet’s center of gravity, determined by the rate of spin; and the center of pressure, the force of the atmosphere on the front of the bullet. When muzzle velocity increases, the gyroscopic stability increases, but air pressure on the bullet also increases. The two forces almost counteract each other, with a slight edge going to faster spin.
I have loads worked up with varget, but aa2230 and aa2520 are always available local, haven’t shot my 2520 75 gr hpbt rounds yet, but should be slightly higher velocity than varget for the same charge.
i forgot about that calculator and found something quite interesting… i ran it while playing with the temperature, barometric pressure, and velocity it came out green in certain instances and yellow in others, but never red. it seems like a 1/9 twist is right on the edge of too slow. eventually when everything cools down, i might grab a 1/7 or 1/8 twist barrel for extra insurance. but im definitely going to try them out now.
That’s a good point.
The article mentioned above noted that a stabile bullet in one season may not be so in the opposite season.
I went back and read all the profiles… None of the descriptions include any benchrest victory claims.
The change in velocity due to barrel length does not always compensate for barrel twist rate. When comparing the effect of twist rate and barrel length I shot 68g & 69g projectiles out of my 16" 1:9 twist AR carbine barrel and 26" 1:12 twist bolt action barrel.
I could normally shoot 1-1/2 to 2 MOA groups out to 200 yards with my 16" barrel carbine and 68g reloads. I fired some of the loads out of my bolt action rifle and could not get on paper at 100 yards. At 50 yards not all of the rounds were on paper and most of those that were on paper went through the target sideways. The extra 10" of barrel length did not compensate for the slower twist rate.
You never know until you try.