PLEASE HELP with 6 mm br

[cheek9075]

i have a new 6 mm br, just getting started and need advise on what to do. can not gett good groups.

 

[savet06]

Cheek9075,
Best way to get the help you need is to give us specifics on the rifle - custom or factory - barrel twist, etc
loading procedures - loading your own or factory, if you are loading your own what charge,s), bullet weight, seating depth, neck tension, etc...
have you checked your scope mounts, action screws, bedding, etc..
What type of groups are you getting? horizontal or vertical

There's an awful lot that can go into not getting good groups.
Once you lay the foundation I guarantee that you will get good suggestions from this site.
This should get you started on the right path,
Mike

 

[Travelor]

First of all, you have come to the RIGHT PLACE, welcome. You will come to love this Forum and the 6mm BR cartridge - I know as I have 3 of guns in this cartridge and my wife shoots one.

Second, read the article on 6mmBR at http://www.6mmbr.com/6mmbr.html

Third, take a deep breath and start shooting. Most people find that a 107 gr Sierra MatchKing and 30 grains of Varget shoots quite well, but it is a load that you need to work up to as it is at the upepr pressure levels.

Let us know the specifics on your gun and what we can do to help specifically.

George

 

[cheek9075]

sorry for lack of info, this rifle is getting to me.

this is a factory 700 action that has been worked, lugs have been lapped and face has been trued, it has a custom kreiger barrel, stock has been bedded and still has factory trigger, but it has also been worked, very nice trigger for factory. i have a weaver 36 power scope on it.
it has been chambered to .270/.269 inch on neck. brass is norma which has been shaved to .268 inch on neck i am using redding type-s dies, with a bushing to make for a "perfect" fit.
i have loaded 75 gr v-max with 27.5 gr varget powder, with a fed 205 primmer. bullet seated to lans. with this load i got 1/8 inch 5 shot groups at 100 yards. i was very happy, so i loaded 60 rounds for a match. the day i shot the 1/8 inch group it was around 80 degrees with no wind. at the match i shot 2 inch groups, temp was around 60 degrees with calm to no wind, perfect day for a shoot.
why did my group get so bad? was it temp change? i played with it yesterday, is was about 35 to 40 degrees, i tried 75 gr v-max for min to max with varget powder. min being 26.5 gr and max 30.8 according to hornady load data. i also tried n-135 with no luck. i have also tried 90 gr berger hp with n-540.
don't really know where to go next. reading load data on net people have posted 75 gr v-max with varget higher than hornady max. is this ok to do, should i try pushing load a little fast? or am i just missing something little.

 

[janderson0]

There will be a few more questions, first what twist is the barrel?

I have found that v-max bullets do not all measure the same dia. If your chamber is closer to .269 and your loaded rounds are .268 some might be a little too tight depending on bullet size and if your necks are are all exactly the same. A little difference on neck thickness combined with a little bit fat bullet could be an issue.

Jim

 

[treeman]

cheek Try and turn the brass another .001" ie .267. I think that will solve your problem. just my opinion. treeman

 

[cheek9075]

barrel is a 1:10 twist. i so a "tight" fit is not always good? and should i puch bullets a little fast, go over the hornady max?

 

[HPMike800]

Your necks should be cut such that the inside of the case neck should read about 0.245" after firing. That should be about 0.267" - 0.266" loaded. You might have tight neck problems.

Your 90bgr Varget/N540 load should have a good load point somewhere. I have a load in my 1:8tw barrel with 95SMK's and 30.5 of Varget that's 1/2min. I would think 30.0 to 31.0 of Varget will find something. Work up of course.

Mike

 

[MarkS]

cheek9075,

First thing. you said,bullet seated to lans), if you are just touching, this can cause problems. One bullet will touch, the next one will not. Try into the land, so the riflings make a square mark on the bullet. this is about 0.020" into the lands. then you can work from there. I seat everything 0.010" to 0.020" into,back off loads and work up.



Check your necks, sounds like you need a little more room. I shoot a No trun neck on my 600 yds Benchrest guns 0.272" loaded round will run 0.2685" that is a good 0.003"

It could be the lot of bullets,get some good Benchrest bullets, Berger, Barts, etc. I shoot 68gr or so starting with 32gr N135, this will shoot in every 6BR I have owned.

Mark Schronce

 

[cheek9075]

well for the most part everyone seems to think it could be neck, so i'll try it first and try seating bullets in to lands. i will also try loading from min to max agian. it looks like everyone likes to load a top end of load.
thanks for all the help. will be awhile before i get a chance to play with it agian, but i will post back with results
thanks agian, it nice to find a place where you can ask questions and get good results, best place and best people i'll ever had contact with.

 

[Twud]

I agree, I think your neck size if fine. Your charge is light. I shoot the same bullet with 31.5 grains and get groups in the high 2s/low 3's. They will not shoot as well as a true match bullet.
I've gotta' agree with Lynn there's something more serious going on. Lose scope screws come to mind.
I didn't know it was possible to get a 6br to shoot 2" groups.

 

[cheek9075]

i have to say i thought something else is wrong. i have a friend that has a 6 br cut with the same reemer. he shots norma brass, cut to same as mine. it shoots less than 1/8 inch at 100 yards, using 66 gr berger with 32 gr of n-135. my rifle should do better than it is, i have remm bases with weaver steel rings. it is a weaver 36 power fixed scope.

 

[cheek9075]

lynn
thanks for the help, i have ask this question before and never have gotton a firm answer. people have posted on the net, 6mmbr, loads that are over max loads, take for example 75gr v-max with varget, if i remember right, max load in hornady is 30.8 gr of varget, web page goes over that. i have went form min to max and with varget and 75 gr v-max with best group at top end. thought about going hotter to see if it help but didn't want to chance things, like i said i'm new to this, and trying to learn what works and what will get you hurt.
i have taken rifle apart and clean it as i do every time i shoot, stock is bedded with full contact, barrel is free, nothing touching, scope mounts are tight, along with scope.
i have order new bases for rifle and new mounts, davison mount and kelby 2 screw rings from sinclair, waiting for delivery. do not yet have an other scope to try but working on that, have purchased a luepold target scope.

what do you mean by seating bullet out as far as i can? touching lands?? or where i am pushing bullet into lands.

 

[cheek9075]

lynn
ok i under stand about the powder charge, one more question is why seating depth have such a big part of it? if you are seating to lands and using bolt of rifle to push bullet back into case, i don't understand why you would need to go .010 or .020 inch into the lands, why does it matter when bolt is closed does it not put the bullet in the same place no matter how much you set it out?
how accurate does powder charge need to be? i am using volume charges. i have checked drops, they vary say from 29.9 to 30.1, i was shooting for 30 gr even. will .2 gr of powder make a big difference. do i need to start weighing each charge with a scale to make sure i get 30 gr.

 

[Twud]

In order to eliminate 1 more small variable I weigh my charges. I use my meter to throw them a grain light and the move the pan to my digital scale and trickle the rest. I've been told this is not necessary with an accurate meter, but it makes me feel better knowing that the charges are the same. I guess if I were loading rounds by the hundreds I might feel different.
I'll leave the answer to your seating question to those more knowledgable than myself. I've always assumed that by seating into the lands you are actually pushing the bullet into the case and increasing pressure.
With Weatherbys you have no choice but to jump them.

 

[cheek9075]

lynn
ok i now i have a better understanding of what to look for. i had no ideal until now on how to even start finding a good load. i think i have tried to change to many thing at once causing me more problems than i thought. i have only loaded for factory rifle before to try to save money, i was happy with 1/2 inch groups, not really hard to hit on. but this is a little harder to do. i had no reason before to try to find that "perfect" spot.
how much weather,temp) will cuase a group change. i have posted before i have gotten a 1/4 inch group at 100 yards with the first load that i tried, 27.5 gr varget with 75 gr v-max. temp was about 80, when i shot again temp was about 50 will that change groups that much?
if i find a load and then work on seating depth, and it does not get better, where do i go from there? i think i understand about why changing seating matters. the bullet goes back into case the same everytime, but the tension on the bullet changes due to the neck tension, i guess i would use a small bushing in the sizing die to change neck tnesion on the bullet, tring to get closer to a more repeatable pressure.

 

[cheek9075]

lynn
i am in south west va. a little town called ewing va. western most tip of virginia.
there is a match next week down here. i hope to try loading some maybe next week. my friend is using n-135 powder with 66 gr berger. i would like to try to and shoot varget, n-135 seems to be harder to get now of days. i can find varget at most gun shops around here. i will try what you have told me and let you know how it goes. i hope it all goes well.

 

[expiper]

Hi John....you have the best advice out there....several of these responders are active competitors,not just puter shooters).. I too have the best accuracy with the bullets either in the lands .020" or out of the lands .020" like Lynn sugested......I dont use Varget ...but it does work well and the charge data given is what works....the main thing is either have em all touch or all NOT touch....good luk...Roger

 

[cheek9075]

thanks lynn
you have helped alot. explained alot. got my new mounts in and put them on rifle last night. looks like they are all right. hope everything is alright anyway. i am going to load some new wekk if i get a chance. i will let you know how it all works out. not going to give up on it at this point. i would really like to see this rilfe shot.