how light of a bullet will shoot out of a 8 twist

[GT Accuracy]

i have always followed the motto of tuning your barrel to the bullet you want to shoot. That said with so many people building 8 twits for competition - how light of a bullet would you shoot (if throated correctly) out of an 8 twist.

i have read as light as the 60's but some seem to think that anything less than 85-87 will be overspun


thoughts / beliefs?


Greg

 

[lpreddick]

an 8 twist will "shoot" any bullet you run thru it. several of mine spin apart varmint bullets of light weight...the thin jackets are not designed for rapid spinning. i believe the twist rate of a barrel will shoot specific bullets most accurately. fast twist prefers light while slow twist likes heavy. there are exceptions but this is just a general observation.

 

[GT Accuracy]

yes - follow you.

i understand that the thin jackets will spin apart but that's exactly what i am trying to get a definitive on.

a buddy of mine wants to shoot varmint bullets out of his 8 twist. I keep telling him to be safe and use the 87 gr v-max's as i think they are big / strong enough for that spin rate but the lighter ones will seperate.

just curious if anyone did a study on just how fast you can spin a 75 gr or lighter 6mm bullet

i typically like 75 out of a 14 tw or 13.5, 87's out of a 10 tw and anything heavier out of a 8 twist

 

[jhord]

Greg- I have shot lots of Berger 80's out of my 8 twist 6BR at ~3050 fps, no problems. I have also shot quite a few 68's, I can't find my data card handy but I want to say ~3200. No poofs. Also I have shot 80's out of my 6 Dasher at ~3400.

 

[Shynloco]

i have always followed the motto of tuning your barrel to the bullet you want to shoot. That said with so many people building 8 twits for competition - how light of a bullet would you shoot (if throated correctly) out of an 8 twist.

i have read as light as the 60's but some seem to think that anything less than 85-87 will be overspun


thoughts / beliefs?


Greg

Greg,
IMHO, oft time....opinions are like navels...everyone has them. I let a given rifle tell me what she likes best at a specific distance and barrel twist opinions are deceiving and based upon experiences using a specific barrel and or weapon. My Savage Benchrest Model 12 (1:8 ) loves 68 gr Bart's bullet at 100 yds which is all I shoot anymore. Depending on whether I'm shooting a Bart's 68 gr FB (Ultra) or even a 68 Bart's HPBT, I use different a powder that give me the best results accuracy wise with each type of bullet. Remember, what works in one rifle, may not work in another rifle even if of the same make or model. That's what "testing" is all about. Just my 2 cents worth.

Alex

 

[expiper]

OP,,,,I have shot many 62-68 gr bullets in 8 twist 6mm BR's(28"bbls.),,,,at max vels'.....I shoot mostly Botique premium bullets and have had no jacket problems,,,(I have shot Sierra 60's and 70's and 75's with no truble and good accuracy--the Hornaday bulets did NOT like the Hi vel and fast twist,groups were bad) ,,,generally the vels. are around 3600fps (if your doing a .243 AI or equal there may be problems but not in a 6mmBR)(since cal was the ?,,but chambering is a biggie,,,an Ackley type hot rod will shoot much faster and I have never tried lil'bullets in one of em!!),,,I use the same powders as in short range (22" bbls) with the 60-75gr bulets ,,,when I get to 80gr I switch to the appropriate powders for the larger 6mm bullets,,,,Roger

 

[jrm850]

Yesterday I shot a couple of 58 V-Max out of an 8 twist Dasher at about 3600fps. They made round holes at 300yds but that's about all the good news I have.

 

[doc gordon]

lpreddick says fast twist prefer light bullets and slow twist prefer heavy bullets ! I think he has this backwards .

 

[mr45man]

lpreddick says fast twist prefer light bullets and slow twist prefer heavy bullets ! I think he has this backwards .

Yes its back asswards

 

[jonbearman]

Thanks for clarifying about fast and light etc.I thought I was going crazy.

 

[Steve Blair]

I shot a lot of 58 V-Max Moly out of a 9" twist 6mm Remington while pursuing the wily Crow. If it was really hot, I cut them back to about 3900. Most of the time, a stiff Varget load drove them at 4050. They were accurate and made it to the target every time. Unfortunately, none of the targets are available to testify. In fact, not much of the targets could be found at all. [br]
The easiest way to find out what your barrel will shoot is to give it a try. The worst that can happen is a day at the range and that isn't bad.

 

[BradY]

I shoot 40 and 50gr nosler BT's out of an 8 twist 223. At 100yds they make awesome groups. But out past 150 the performance isnt very reliable. I found that shots are going high and low by a good foot or so. It was only recently I found this out after putting up with missed long shots for ages that I thought was just me. Now 8 twist barrels are for long and heavy bullets in 223 and 6BR. From what I have read because the bullets are spinning so fast they try and resist the natural force of gravity to angle the nose down and drop over range. Thus bullets end up flying crooked. At close range its no problem, but long range I have trouble getting consistent hits and this theory does sound about right. Never had any bullets let go and disintegrate on me. I hear the speer TNT's are bad for doing that and the nosler custom comp bullets too

If you want a long range varmint rig then definitely use 8 twist, if you want a varmint rig for up to 500yds or so then I would get a 1:10 or 1:12 and shoot the 58-87gr bullets in 6mm.

 

[CatShooter]

From what I have read because the bullets are spinning so fast they try and resist the natural force of gravity to angle the nose down and drop over range. Thus bullets end up flying crooked.

There is no natural force to angle the nose down. They are little gyroscopes and do not change the angle that they start with.

 

[lpreddick]

sorry i must have had a brain f__t, again! fast twist...heavy, slow...light.

 

[North Fork]

I shoot the 80gr sierra pistol bullits out of mine and they work great on prairie dogs

 

[savagedasher]

I tried some 87G v max with my dasher with a 8 twist 35g varget Ouick load said 3430fps sub 1/4''was no problem at 100yds.575yd at a 5''gong I hit14 out of15 shots.
Good Shooting Larry