Lightest 6mm Bullet with 1 in 8" twist?

[Ledd Slinger]

I have an up and coming 6XC rifle that I should start testing here pretty soon. Will be a dual purpose deer/varmint rifle. Went with a 1 in 8" twist barrel to whack deer with the 105gr Berger VLD, but was wondering how light of a bullet I can get good accuracy with in that twist rate?

I've heard the 87gr V-Max works well in that twist, but was wondering if I could go lighter? I know boat tail and flat base will make a difference, but open to any style. I keep a supply of 75gr Sierra HP bullets (flat base) that I use in my 6mm Remington that has a slower twist. Just wondering if I could also use them in a 1 in 8"? Thanks.

Will slowing the speeds down help accuracy in a tight twist with a light bullet? Or does that even matter?

 

[jonbearman]

Honestly you can shoot any bullet with the exception of varmint grenades and a couple others that don't seem to shoot as well to me. I normally stay above 60 grain bullets with the faster twist.

 

[Ledd Slinger]

Thanks jon. Are you pushing the lighter bullets up at max speeds? Or do you slow them down a bit to reduce the chance of a bullet coming apart in the bore?

 

[jonbearman]

I don't use thin jacketed anything under 65 grains being the 65 vmax by hornady. I shoot mostly match bullets due to me giving up on varminting in new York.

 

[Ledd Slinger]

Ok. Well these will be varmint style, not target, and the 6XC will give a pretty good push to lightweight bullets. I push the 75gr HP varmint bullets close to 3500 fps in my 6mm Rem. Really wondering if it's ok to try similar speeds in my 6XC without fear of a meltdown when the barrel gets hot from multiple shots. Thanks

 

[snert]

I use a stout load of 8208 and a 70 Grain BK and it is more accurate than any load of the various heavies...8 twist Hart

 

[abishai]

If the bullet goes POOF , back off the load , if it doesnt , push it harder . Varmint advice . For deer use the heavies with judicious marksmenship

 

[Ledd Slinger]

I've only ever had one bullet go POOF. It was when I was working up at max speeds in a varmint rifle by .2gr increments to see how fast I could make it go. Well when I hit that last .2 over the limit, the 4th shot of the 5 shot group I was shooting came out in a shotgun pattern of molten metal. But it also created such a huge pressure spike the gun blew up in my face. Luckily I was ok, but the gun needed a lot of work to get it shooting again. Including bushing the blown apart bolt face. So that's where my concern stems from. I don't ever want to see a bullet go POOF again.

 

[Ledd Slinger]

I use a stout load of 8208 and a 70 Grain BK and it is more accurate than any load of the various heavies...8 twist Hart

Thank you. I'll see what I can make the 75s do then. Maybe hit 3300 and call it good. That will help barrel life out a bit too. If you dont mind, what caliber are you using and what speed are you pushing the 70gr BKs?

Great quote below you messages by the way

 

[abishai]

The poof game is best played with the absolute lightest bullets for caliber . Varmints go flying, messy pizza midst - good . Your riffle destroyed - bad . If I said that my favorite load is 486 grains of pistol powder behind a 186 grain bullet in a 6br would you try it ........ (this load is not safe , or possible in ANY rifle ) . Gunsmiths love shooters that get their load data from the into-net

 

[Ledd Slinger]

That lesson was learned a long time ago. I know what I'm doing and your POOF suggestion is not an option. Thank you.

 

[AckleymanII]

The 60g Sierra will not go POOF at any velocity, I have shot them at 4400 fps. In my 6ppc and my 6 BR these bullets are almost on par with The very best benchrest bullets, and I made my own BR bullets.

The 55g nosler will not go POOF either, and this bullet has a very high BC for the caliber. Sierra's 55g Blitz king has a match jacket that is sorted for concentricity, it will not go poof either.

H335 and Ball C2 would be great candidates for your light bullet challenge in the ball powder range, and Benchmark would excel on the stick powders.

I will be doing a test in the coming months on this very cartridge with the lighter bullets.

Good luck

 

[Ledd Slinger]

The 60g Sierra will not go POOF at any velocity, I have shot them at 4400 fps. In my 6ppc and my 6 BR these bullets are almost on par with The very best benchrest bullets, and I made my own BR bullets.

The 55g nosler will not go POOF either, and this bullet has a very high BC for the caliber. Sierra's 55g Blitz king has a match jacket that is sorted for concentricity, it will not go poof either.

H335 and Ball C2 would be great candidates for your light bullet challenge in the ball powder range, and Benchmark would excel on the stick powders.

I will be doing a test in the coming months on this very cartridge with the lighter bullets.

Good luck

Thanks so much. That's exactly what I was looking for. Will still proceed with caution of course, but it gives me a little peace Thanks again

 

[Ledd Slinger]

Ok. Well these will be varmint style, not target, and the 6XC will give a pretty good push to lightweight bullets. I push the 75gr HP varmint bullets close to 3500 fps in my 6mm Rem. Really wondering if it's ok to try similar speeds in my 6XC without fear of a meltdown when the barrel gets hot from multiple shots. Thanks

I have 6xc's in 9, 10, and 12 twist. I've shot 68grBT, 70gr NBT's, 75gr Vmax, 80gr Blitz, 87gr Vmax, and 85gr HPBT out of all of 3 of them at one time or the other. From my experience if you're going to shoot the lighter bullets out of an 8twist you will more than likely have to work up a load specifically for the lighter bullets. Based on my experience with my rifles, I think you'll be hard pressed to hit 3500fps out of a 75gr and get good accuracy..... not saying you won't... just surprised if you do. Personally I get the best combination of speed and accuracy with the 75gr and under with the 12 twist.

How much freebore do you have on your chamber? Will it require you to make a big jump to get to the lands? That could be a concern.

If you have a sporter barrel you should be Ok for 5 to 6 shots before it starts to walk on you. And by then you will have bagged your game for sure. WD

It will have a good jump for sure because I'm set up for the 105gr Berger VLDs to hunt with it as well.

I have other rifles where there is a large jump to the lands due to magazine restrictions, but I have never had trouble finding excellent accuracy that way. Even with Berger VLDs I seem to get great results jamming the lands, just off the lands, or even .080- .120 off the lands. Maybe I'm just getting lucky, but I hope this rifle will react the same to my hand loads with a bullet making a long jump. If the forgiveness I've read about the 6XC is true, I expect it won't be any trouble.

 

[Gene66]

I have a 6xc,1in8 twist, 30" barrel. my load for varmints. 87 V-Max .h4350 38,5gr
It is a mild load,good brass life, 3144fps. It works good on coyotes .
Good Shooting
Gene

 

[sundance]

I tried the 75 grain Sierra varmint bullet in my 6 ackley with a 1 in 8 twist.No holes in the 100 yard target. On a 50 yard target each bullet jacket made 3 or 4 jagged holes in the paper.I shoot the 70 grain Sierra match bullet with no problems.Unless you are a prairie dog.

 

[Ledd Slinger]

I tried the 75 grain Sierra varmint bullet in my 6 ackley with a 1 in 8 twist.No holes in the 100 yard target. On a 50 yard target each bullet jacket made 3 or 4 jagged holes in the paper.I shoot the 70 grain Sierra match bullet with no problems.Unless you are a prairie dog.

Ahhhh...See that's what I was worried about. Good to hear someone with experience on the bullet I was planning on using in the same twist barrel. We're you chronographing the load when you shot it? Curious about the speed at which they came apart? And what is your barrel length? Thanks.

 

[1raggedhole]

Good question for bullet mfrs. what is the max rpm for that bullet? I have also seen some 32's blow up out of a 20 practical w 10 twist. If you send those light bullets too fast I guess you will hit the limit eventually.
Example: 3500 fps * 720 / 8 twist = 315,000 rpm
I have never seen a published limit for any bullet, but they might tell you on the phone.

 

[Ledd Slinger]

Good question for bullet mfrs. what is the max rpm for that bullet? I have also seen some 32's blow up out of a 20 practical w 10 twist. If you send those light bullets too fast I guess you will hit the limit eventually.
Example: 3500 fps * 720 / 8 twist = 315,000 rpm
I have never seen a published limit for any bullet, but they might tell you on the phone.

Thats exactly what I'm looking for! Though nobody usually does the RPM calculation, they just say speed of the bullet and twist rate of the barrel. So I was trying to ask in simpler terms to get more responses. That's why I continue to prod folks responding about their muzzle velocities. Doesn't even really have to be a 1 in 8 twist, though I would prefer that twist. As long as I have some sort of twist info from the posts to get an rpm solution, I then have something to go off of to play with on the velocity of the equation with an 8 twist.

 

[snert]

I use a stout load of 8208 and a 70 Grain BK and it is more accurate than any load of the various heavies...8 twist Hart

Thank you. I'll see what I can make the 75s do then. Maybe hit 3300 and call it good. That will help barrel life out a bit too. If you dont mind, what caliber are you using and what speed are you pushing the 70gr BKs?

Great quote below you messages by the way

Hey Led,

I am shooting a 6mmBR with a 28 inch HArt 8 twist, 70 Grain BlitzKing and my load is 32.5 grains 8208 XBR with a standard primer. No pressure issues, Hart custom action.

And thanks for the compliment.

Snert