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Find the lands (jam point) in semi automatic

With an SD of 8 and a 1.5" five shot group, you're doing reasonably well for a semi-auto with a difficult trigger, mediocre at best factory barrel, an action not conducive to accuracy and a forearm imparting all kinds of random pressures and vibration as the bullet is on it's way.

At near maximum magazine length OAL, I don't think you have much to gain by experimentation with seating depth. I would suggest finding a gunsmith to improve the trigger and perhaps free float the forearm. Then you can experiment with various torque settings on the forearm screw at the range. If you get those rifle tuning things in line, then perhaps a little more load development will bring you down nearer to MOA.

Keep in mind, as these types of rifles get hot at the range, they start throwing shots all over the place. If you're going to do tuning and load development that's meaningful, you've got to keep the heat down by resting it between groups. When I work with this type of gun (and I have), it's best to take two or three other firearms along to shoot while you've got your Browning BAR cooling in the shade between three shot groups. I'm telling you from experience, if you get that gun all heated up, your tuning and load changes are going to be random, unrecognizable and non-repeatable with a cold/cool bore.
Your right about the heat I’ve been trying to single feed for groups and letting it cool between shots but today I shot five shot groups and then letting it cool after the group. I have now managed to get 0.81 moa and extreme spread of 13 I’m hoping to find a node tomorrow by seating deeper
 
The case length for the empty brass is 2.494", trim-to length is 2.484, more or less.

If you get a chamber length gage, which looks like a little plug that goes into a shortened case and helps you establish the length of your chamber to the end of the neck, then stick to the above.

https://www.sinclairintl.com/reload...s/sinclair-chamber-length-gage-prod32925.aspx

Also, there are a few battery powdered chamber chillers or coolers that blow air through your chamber to cool the rig off faster, that are worth looking into when testing sporting rifles that heat up fast. This is just an example.

https://www.chamberchiller.com/
 
Measure your chamber, write it down and refer to it often. Use those figures to tell you when and if you need to trim.
And just because you CAN jam into the lands, doesn't mean you should.
Knowing and doing is two different things.
I did just because I got the "You'll shoot your eye out" thing from some of the older hard headed know it all shooters. :rolleyes:
Same when I put a round in the chamber on my M1A, tripped the bolt release "without" the mag installed. BANG!! Won't be doing that again. :eek:
Was told the gun was JUNK, needed to be checked out by a gun smith and was just waiting to blow up and kill someone. :oops:
That was about 2K rounds ago. Acts like a Timex watch. Takes a lickin and keeps on tickin! ;)
Don't know everything but didn't get this old by being stupid either. :)
 
My case was 2.480 new just full sized before use. They are between 2.487 and 2.489 right now I’m not going to bother with trimming right now. Thanks for the awesome advise
 
I’m .010 under mag length right now today I will seat deeper .010, .020 and .030 I’m hoping to see a node somewhere there and then seating 0.003 increments around that node and maybe getting the groups tighter i hope
 
I’m .010 under mag length right now today I will seat deeper .010, .020 and .030 I’m hoping to see a node somewhere there and then seating 0.003 increments around that node and maybe getting the groups tighter i hope
If you start at .010 and move in .003 increments I can almost guarantee you'll see something by time you get to .030.
 
On gauge cases you understand that’s not ammo right?
Ok. I have had a 300 WM BAR for 25 years. Never saw a need to use pliers in the reloading process.

And, like others have indicated, magazine length is going to dictate maximum coal. When it’s all said and done, you will likely find that 1-2 moa is the best you will get out of it, and you can make it shoot 3 moa with the right load.
 
Ok. I have had a 300 WM BAR for 25 years. Never saw a need to use pliers in the reloading process.

And, like others have indicated, magazine length is going to dictate maximum coal. When it’s all said and done, you will likely find that 1-2 moa is the best you will get out of it, and you can make it shoot 3 moa with the right load.
You miss read a lot. I have since post managed a 13 spread, 6.6 SD and .810 moa. I think my bar and yours are much different. Maybe it’s the 25 year difference. 5+4=9 so does 7+2
 
If you start at .010 and move in .003 increments I can almost guarantee you'll see something by time you get to .030.
Right I understand. I was just thinking it might be a short cut the way I wanted to do it but it may not be smartest. Probably better to seat down in .003
 
Right I understand. I was just thinking it might be a short cut the way I wanted to do it but it may not be smartest. Probably better to seat down in .003
Seating nodes will roll in and roll out.
You'll see the sweet spot when it happens.
I believe you'll see 3 good seating depths between .010 & .050.
Don't ask my why it does this, that I couldn't explain, but it does.
It's really cool to watch and see it happen while your shooting.
 
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Seating nodes will roll in and roll out.
You'll see the sweet spot when it happens.
I believe you'll see 3 good seating depths between .010 & .050.
Don't ask my why it does this, that I couldn't explain, but it does.
It's really cool to watch and see it happen while your sh
You miss read a lot. I have since post managed a 13 spread, 6.6 SD and .810 moa. I think my bar and yours are much different. Maybe it’s the 25 year difference. 5+4=9 so does 7+2
I am sure I do.;) If pliers work for you. That’s great. Glad you have been able to get it to shooting under 1 moa without much trouble. Me and several of my friends have not had such stellar results. Maybe we should refine our methods. :)Be careful and straight shooting.
 
If you're floating between .8 and 1.5 MOA,you've done very well in a sporter barrel semi-auto.With a low velocity spread,you'll be able to do anything you need to do with a hunting rifle in 30-06.I would bet all you get done trying to better that kind of performance is waste powder and bullets.Any production rifle that does better than a good honest 1 MOA for 5 shots is a decent rifle.The distance from 1 MOA to .5 MOA is long and uphill.
 
AbeS, A little food for thought... along the lines of following the herd or thinking for yourself...

When you consider that innovators have often gone up against the grain when they created their paradigm shift, I would never tell anyone their ideas are not worth trying just because they go against the grain.

However, along with that concept I will add the corollary which comes into play as often as not, and that is that when you compare your resources to those of all the folks who compete in your topic, you have to asses whether or not trying things a different way has been explored before your attempt and if the costs will break you.

Many semi-automatic platforms have existed for nearly 100 years. Governments have been interested in them for obvious reasons. Sporting versions are as old as the military ones.

By trying to turn a Browning sporting BAR into a match grade performer, you may find yourself up against the size of the challenge it was when the Garand, M-14, and M-16 went down that path. It was certainly done, but it also took lots and lots of work to turn those platforms into match guns to say the least.

Now your BAR is a fine piece and there is nothing wrong with attempting what you are trying to do with it. Just be aware that light-weighted sporting guns might or might not adapt well to mid or long range match gun use without lots of hard work and a lot of luck too. All of those words are a preamble to the only advice I will add.... think about trading this one for one with the HOTS on the muzzle if you are going to be picky about performance. Keeping one of these in the tuning node with that HOTS was much easier than having to load for weather changes.
 
I am so disappointed. I spent a lot of money on this rifle scope reloading range trips etc and it won’t group. I shoot better groups with my fal with peeps sights. At 500 this will not shoot any kind of group. I had a really tight 3 shot group earlier today at 100 but right now im thinking it meant nothing. I’m pretty defeated. I can’t believe browning will sell crap like this. I’ll try it tomorrow one last time before I take the scope off and burn it
 
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My old work partner has had many BARs, he traded BARs Browning bolt rifles and German Weatherbes. he had a BAR that would not shoot and it was near new, so he sent it back when it was returned it had a factory target with a great group. He went out and bought the same factory ammo that was written on the target and all was well. When he was putting the gun in the case when it first came back he noticed the case zippered up better, and he told me the barrel was 1/2 inch shorter. I wasn't too long after that that Brownings started being made with the boss system. He talked to the factory and they confirmed barrel harmonics were altered with the 1/2 inch removed from the barrel. if i wanted mine to shoot groups better I would try a BOSS system or cut the barrel a little and try a bunch of different factory ammos.
 
I am so disappointed. I spent a lot of money on this rifle scope reloading range trips etc and it won’t group. I shoot better groups with my fal with peeps sights. At 500 this will not shoot any kind of group. I had a really tight 3 shot group earlier today at 100 but right now im thinking it meant nothing. I’m pretty defeated. I can’t believe browning will sell crap like this. I’ll try it tomorrow one last time before I take the scope off and burn it
Ok,…… we have all tried to tell you it’s a hunting rifle and nothing more!…. It’s not a piece of crap!… it’s a Browning!…. John Browning made the best guns in the world however you can’t compare a $800 hunting rifle with a $6000-$10000 fully custom br rifle. Now with that said what scope and mounting system do you have on that rifle?…mounts? And whatnot?. You have been getting it hot with those five shot groups do you have a carbon ring starting?… have you looked in the bore with a scope?… is it copper fouled?… is the rifling sharp? What does your crown look like?….. what setup do you have for shooting?… solid bench,…. I mean solid!… sand bags? Bipod?.. shooting rest?.. rear support?.. my M1 Garand shoots between 3/4 and 1” it might do better if I rung it out more but it’s plenty good for what I use it for and it will easily hit my 600 yard gong are all your screws tight and correctly tight?… there’s a lot to this sport AbeS we’re all here to help ya but you can’t pull a loaded 24’ stock trailer with a corvette and you can’t beat the corvette up a windy grade with a dually dodge pickup . Let’s get this BAR shooting somewhere in the 1moa range and if you want to shoot smaller groups with a hunting rig build one from the ground up and it will shoot those 1/2 Moa groups your looking for
Wayne
 
I am so disappointed. I spent a lot of money on this rifle scope reloading range trips etc and it won’t group. I shoot better groups with my fal with peeps sights. At 500 this will not shoot any kind of group. I had a really tight 3 shot group earlier today at 100 but right now im thinking it meant nothing. I’m pretty defeated. I can’t believe browning will sell crap like this. I’ll try it tomorrow one last time before I take the scope off and burn it
Sorry to hear about your frustration. The rig is fine for the main purpose, which is to take the edge off of the recoil and offer a good follow up shot.

Not to discourage you or to start up the debates about what you can possibly know from a three shot group, but don't give up so easy.

Hitting Kill-zone sized targets at 500 yards with a light sporting gun takes some experience and skill, especially when there is any wind. Any time I have hunted PD, coyotes, or badgers in the Dakotas, there has always been some serious wind.

It sounds like you have some background, but do you have much background out past 200 yards in wind?

Tell us what you did in terms of group and stats at 100, and then what you saw at 500?
 

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