6PPC Accuracy vs. 6BR--Short Bullet vs. Long

[Forum Boss]

DANTEC
It seems that most serious shooters get best accuracy with 6 BR Norma using a heavy, high BC bullet because high BC make shooting easy in the wind...

So who wants to share groups /reloading recipes / gun components / chambering details for 100/200/300 and 600 yards or meter. That's the best way to compare real accuracy potential of the two cartridges side by side. The 6BR is now perhaps another way to shoot good aggregate due to being easier to shoot in the wind.
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Riverine
Dantec--I think this is a question we'll see sorted out in the next couple of seasons. Right now it seems to be a toss-up at 300yards/300m. The 6PPC guys are running their little 62-68gr pills all the way out to 300. But the CISM shooters in Europe are Running the 105s and 107s at 300m.

Reading the articles by Danny Reever and Mark Schronce, it looks like the long Flat-Base bullets definitely can do the trick at 300-600 yards if the conditions are right.

I think it will be very interesting to see what happens at the 600-yard matches and see whether the short bullets can win consistently. As to the 6PPC at 600, I've talked to a couple guys who tried with 14 twist PPCs at that distance, and I was hearing things like "pushing the envelope", "on the ragged edge", "gonna use a Dasher next time."
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George Ulrich
I'm shooting a 6br for first time in a unlimited bench gun 14 twist, 68gr bullets. What can be expected for velocity with what powders--this for 100 & 200 yd?
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dreever
Dantec--In comparing my 6BR ten twist to my 6PPC 14 twist over the course of two years I've come to these conclusions.
At 100 yards the PPC will shoot smaller groups over the long haul. At 200 yards this may still be true--until you factor in the wind. Then those 90 grain Berger Boat tails with a BC of .410 begin to show their stuff. They will shoot phenominal groups! You really must try this bullet on top of 30-31 grains of Varget fired by the CCI 450.

I've shot my PPC in matches at 500 meters. Again on a calm day the PPC will shoot respectably. However in any kind of wind a 68 grain bullet with a BC of .271 @ 3350 fps will fall on its face compared to the Berger 95 grain VLD with a BC 0f .524 @ 2981 fps. Use any balistic program and run the numbers, you'll see for yourself.

Having said all this when it comes time for me to re-barrel my 13.5 pound 6PPC for short range benchrest it will be a 6BR in a ten twist using my current Dave Kiff reamer, and I'll probably shoot the 90 BT in it to 300 yards.
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DANTEC
Basic idea is to build a full length 6 BR body,not a SBR) to be in regular pressure because most PPC shooters load at high to very high pressure level 6 BR with reguler 0.06 throat length / 0.269" neck,just neck turned lightly to remove high spot) this combo with 1 in 12 will allow to shoot as 80 Euber or even 90 Berger. A 1:11 would be a good multi-purpose choice.
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lynn
Guys I will try and get Ray Miketa or Cheechako as he sometimes posts as to answer this question. He shot a 6ppc with a longer throat at the NBRSA 600 Yard Nationals in Sacramento this year and did very well with this combination.

 

[6Dasher]

Hi,

DO you think the 90BT will be okay in a 1:12 twist? I am thinking of a new barrel for the Berger 88LD and am haging around 1:10 right now. I would love to hear from people who tried the 88/90 in a 1:12 twist...


Jim

 

[HBC]

Danny,

I have a short BR, just a littler more volume than a PPC, that the 6mm, 90 grain BT Berger would likely be a good choice for 600 yard matches. If you don't mind, what are a few dimensions on the 90 Berger BT?

length---
meplat dia.---
ogive length---
boat tail length---
meplat to top of core---

Henry

 

[dreever]

Hi Henry,

Glad to see you posting here on 6mmbr.com
Here's the info that you requested:

length: 1.067

meplat dia: .0079

ogive length: .487

boat tail length: .110

meplat to top of core: .362

Let me know what actual BC you come up with compared to Bergers advertized .410, since they have been rather generous with BC's in the past.

Danny

 

[HBC]

Danny,

Thanks for the dimensions. You gave a meplat diameter of 0.0079", that would be almost needle sharp. I suspect you meant 0.079". If 0.079" is correct for the meplat diameter, that is the reason I am getting a much lower estimated BC than Berger gives. My estimate is a BC of 0.32.

Henry

 

[dreever]

Henry,

OPPS! One to many zero's! Yes it is as suspected lower than Berger's advertised .410, but you really have to try that bullet. It is phenomenally accurate.

Danny

 

[Anmlsrdelicious]

Great topic, sorry I'm coming on board late. I'm setting up a LV 10.5lb rig with a 12 twist, so that I can shoot the 80gr bullets at 200. I'm betting that I will gain an edge over the ppc and the 68gr bullets from thier 14 twist with any wind. I'm going to be tinkering with the Fowler 80, and Berger 80.I wish others would jump on board and offer 80gr bullets.

 

[shcal]

Great topic! I would like to ask all about an idea I have. First of all, I do not competitively shoot, I shoot small four legged creatures with tails known around hear as ground squirrels,really pests). I purchased a used HV 6PPC last year to give it a try because I've heard so much about their accuracy, and it is true, they are very accurate. However, most of my critter shots are at ranges from 150yds to 500 yds. The PPC is great for under 250 yds but is really challenging beyond that range. Oh, did I mention it is always windy here? Typical day is 10mph-25mph with many gusts to 35-45mph. The 68gr bullets have a tough time with that kind of wind. OK, sorry for the long winded preamble, here's the question, is it worth while to make the gun a switch barrel into a 6BR 10 or 8 twist barrel? Will I see a VERY marked improvement in accuracy over distance in this wind? What weight bullets do you suggest for critter popping?

 

[rhaney2]

Great topic, sorry I'm coming on board late. I'm setting up a LV 10.5lb rig with a 12 twist, so that I can shoot the 80gr bullets at 200. I'm betting that I will gain an edge over the ppc and the 68gr bullets from thier 14 twist with any wind. I'm going to be tinkering with the Fowler 80, and Berger 80.I wish others would jump on board and offer 80gr bullets.

The ppc and fowler or any good custom 66-68 grain bullets will eat you alive at 200 yards in a ppc.
I don't mean to bust your pride and you may get the 80's to work,but a 14 twist ppc is not going to be beat as time and my self have tried.
The 6 br is a 300 to 1000 yard killer in good conditions but at the shorter ranges of 300 or less,the ppc has a edge in accuracy.
It's a shame the 6br didn't come along in 1974,if it had,we would have never heard of the ppc.
anyway,good luck with the 80 grainers,the 66-68 grainers will shoot just just fine in the 12 twist and may give you an edge at 200-300 yds against the 14 twist ppc's.