6BR fast twist with lighter bullets?

[Forester]

Not new to reloading, but I just started putting together a 6BR and came across a deal on a new Ratchet rifled Shilen 8 twist 6BR barrel.

How well is this likely to do with the lighter 69-70gr Bergers?

This gun is primarily going to be a varminter and punch paper out to 5-600 yards or so.

Thanks!

 

[Preacher]

It will shoot the light weights better than a slow twist will shoot the heavies...

 

[Forester]

It will shoot the light weights better than a slow twist will shoot the heavies...

Well, that's a start I suppose. Would the 80gr Berger or Noslers be a little better choice?

 

[6BRinNZ]

hey Forester, it probably depends on your expectations. I shoot 75s in an 8 twist and have just finished a ladder for Nosler 80s that I am pleased with as well.

 

[Forester]

hey Forester, it probably depends on your expectations. I shoot 75s in an 8 twist and have just finished a ladder for Nosler 80s that I am pleased with as well.

Expectations...I would like to be able to run the 70s at 3200+fps from a 26" barrel or the 80s at 3100+ Accuracy wise, half minute or better out to 500yards assuming the gun is built right...that part is on me.

That seem reasonable?

 

[Coleridge]

Expectations...I would like to be able to run the 70s at 3200+fps from a 26" barrel or the 80s at 3100+ Accuracy wise, half minute or better out to 500yards assuming the gun is built right...that part is on me.

That seem reasonable?

Seems realistic to me. Although you will be able to get the 70's right much faster... I had a 26" 10 twist (we just took the bbl off last night) that would do that. It actually shot 65gr Vmax the best of all the varmit type bullets. I don't think you will have a proble shooting 70's with an 8 twist.

 

[RonAKA]

Expectations...I would like to be able to run the 70s at 3200+fps from a 26" barrel or the 80s at 3100+ Accuracy wise, half minute or better out to 500yards assuming the gun is built right...that part is on me. That seem reasonable?

My 26" 12 twist gets 68 grain bullets up to 3500 with Varget. 3400 gives better accuracy. Varget will also get 80's up to about 3200, but it shoots better at 3100.

The concern about the fast twist is not likely the twist, but the throat length. If the chamber is cut to give you room to handle the 115+ grain bullets, then it may be too long for the shorter lighter ones. The throat in my 12 twist is longer than it should be. It shoots the 68 grain very well, but is terrible (1.5-2" groups), with the same design bullet at 62 grains.

 

[skany]

i have a 74freebore & its super acurate with 55g noslers @ 3800ish & 105g amax @2900ish

cheers Andy

 

[expiper]

You will have good results as long as you stay with good bullets.....some 75 and under bullets will not take the hi rpm's.....gota try em with your bbl....I shoot Kriegers and used Sierra 60gr-70gr-and 75gr with no problems....and SOME true benchrest (botique bullets) ,problems showed up when I had to jump-em to the lands,,as the case with some of the real short ones......the target will tell what works for U....Roger

 

[Forester]

Thanks for the input all, What I have on hand already are 69gr Bergers, 80gr Bergers, and 80gr Nosler BT varmint bullets. I also have some 95grVLDs but they are not really what I want to use in this gun.

How much jump do any of these bullets usually like? I checked last night and could just reach the lands with the 95s so jamming the others is out of the question.

 

[skany]

I tried 65g vmax today & they also shot in the high 1s

cheers Andy

 

[6BRinNZ]

I would recommend 105 A-maxes if you can get them and can push them to 2900+. I use them for varminting on rabbits and magpies with hits out to 475 yrds and have absoultely no qualms about them being explosive enough.

They are also a very good paper puncher and when running hot 2900+ will get you out to 1000 yrds at a pinch and will fit the longer throat no problem.

I have just settled on a load for the 80 grain Noslers, running at an average of 3087 fps. I use the Redding Instant Indicator to measure the seating depth, so I won't give you a measurement as it will be meaningless, but I will be loading a bunch for this weekend so I can send you an over all length if you like? This will give you a ball park to work from.

 

[Forester]

I would recommend 105 A-maxes if you can get them and can push them to 2900+. I use them for varminting on rabbits and magpies with hits out to 475 yrds and have absoultely no qualms about them being explosive enough.

They are also a very good paper puncher and when running hot 2900+ will get you out to 1000 yrds at a pinch and will fit the longer throat no problem.

I have just settled on a load for the 80 grain Noslers, running at an average of 3087 fps. I use the Redding Instant Indicator to measure the seating depth, so I won't give you a measurement as it will be meaningless, but I will be loading a bunch for this weekend so I can send you an over all length if you like? This will give you a ball park to work from.

Do you know the distance off the lands perhaps? I am planning to load some of these this weekend time permitting.

 

[6BRinNZ]

Sorry I dont know the eaxct distance off the lands as I have always found it difficult to get an exact measurement...particularly as the throat wears, all I concentrate on now is the base of the case to the ogive measurment...

Anyways for what it is worth I am jumping the Noslers and I would expect the jump to be .005 - .010. This is based on previous efforts to measure to the lands.

Measuring the case to tip is 2.298, and using the sinclair hex nut the measurment is 2.792.

I just finished a 600 yrd comp using the Noslers today and vertical was excellent (verified by one of the top shooters in the country) until shot 15, then it jumped by 3/4moa, I'm not sure why but I am assuming fowling at this stage. I get a lot of copper on the patches compared to V-maxes, A-Maxes or Bergers.

Anyways hopefully this info is helpful.

Good luck.

 

[Forester]

Sorry I dont know the eaxct distance off the lands as I have always found it difficult to get an exact measurement...particularly as the throat wears, all I concentrate on now is the base of the case to the ogive measurment...

Anyways for what it is worth I am jumping the Noslers and I would expect the jump to be .005 - .010. This is based on previous efforts to measure to the lands.

Measuring the case to tip is 2.298, and using the sinclair hex nut the measurment is 2.792.

I just finished a 600 yrd comp using the Noslers today and vertical was excellent (verified by one of the top shooters in the country) until shot 15, then it jumped by 3/4moa, I'm not sure why but I am assuming fowling at this stage. I get a lot of copper on the patches compared to V-maxes, A-Maxes or Bergers.

Anyways hopefully this info is helpful.

Good luck.

Thanks for the measurements. I am duracoating the 6BR this weekend and as soon as it gets back together I will be loading for it. I think a ladder with the 80gr Bergers and 80gr Noslers is where I will start first.

 

[xring]

I have a fast Twist 0.224 and a fast twist 6.5mm , and both shoot light bullets considerably better than heavy bullets ( not what I really wanted ) . The only way to tell for a specific rifle is to try them out .