I have a 20 BR rifle, and have found that some of my brass chanber tight, and others do not. Any ideas on why this is happening?
20 BenchRest
- Thread starter PAshooter20BR
- Start date
overall case length is good, anything else?
I am new to reloading, how do adjust my die to bump the sholder back? I bought the gun used and it came with a couple hundred cases. My cases that chamber tight are r-p brass that have been fired and are made from either 6mmbr or 7mmbr cases. I also have some cases that are unfired Lapua that chamber excellent. There is a difference in headspace between the two. what throws me off is that some of my rp brass has the same headspace but one case will be tight and the next wont.
Any ideas?
Thanks
Any ideas?
Thanks
You'll find the deeper you get into reloading the more tools you need. With the questions your asking you need to do some reading up on the basics. I'm not sure what equipment you have but essentially you adjust your die down towards your shellholder to size the case shorter.
Info is all over the web for free or find a competition shooter in your area at the local sportsmans club etc. They are more than willing to help thats what different about this sport than others. You can buy a video on reloading try ebay the Sierra TUBB video is good and there are many others. The Sinclair book handloading for competition is excellent.
http://www.sinclairintl.com/cgi-bin/category.cgi?category=BOVS&item=15-845&type=store
I learned it all the hard way by trying.
There can be several things that cause a round to chamber tight.
OAL incorrect causing throat to pinch the bullet in the case
Incorrect headspace ie the shoulder is too tall relative to the base.
Incorrect neck diameter for your chamber neck
Base of case too large for chamber therefore you need a small base sizing die. etc
Start with headspace.
When you set your headspace you need to know what headspace you want. Most use a tool that hooks to a caliper called a stoney point headspace gauge. You'll need a set of calipers. You will typically want about .002" clearance minimum. Highpower will be more benchrest will be less.
http://www.sinclairintl.com/cgi-bin/category.cgi?category=REMTHT&type=store
This can also be used to measure your bullet seating depth also.
Then your going to want to know how deep you seat your bullets there are many ways to measure such.
Info is all over the web for free or find a competition shooter in your area at the local sportsmans club etc. They are more than willing to help thats what different about this sport than others. You can buy a video on reloading try ebay the Sierra TUBB video is good and there are many others. The Sinclair book handloading for competition is excellent.
http://www.sinclairintl.com/cgi-bin/category.cgi?category=BOVS&item=15-845&type=store
I learned it all the hard way by trying.
There can be several things that cause a round to chamber tight.
OAL incorrect causing throat to pinch the bullet in the case
Incorrect headspace ie the shoulder is too tall relative to the base.
Incorrect neck diameter for your chamber neck
Base of case too large for chamber therefore you need a small base sizing die. etc
Start with headspace.
When you set your headspace you need to know what headspace you want. Most use a tool that hooks to a caliper called a stoney point headspace gauge. You'll need a set of calipers. You will typically want about .002" clearance minimum. Highpower will be more benchrest will be less.
http://www.sinclairintl.com/cgi-bin/category.cgi?category=REMTHT&type=store
This can also be used to measure your bullet seating depth also.
Then your going to want to know how deep you seat your bullets there are many ways to measure such.
Thanks for the tips, I haven't been around competition reloading that much, but have been around my father who loads large quantities of pistol ammo. These two world are very different. It is definately a tedious process, but much is learned along the way.
Forum Boss
Administrator
R-P Remington brass is softer than Lapua brass. Also they work-harden,lose elasticity faster). Chances are the cases have just grown faster than your Lapua cases.
The need to bump the shoulder may be there, but you really need to find out why your cases are hard to chamber first. I suggest you get a magic marker, and cover the body of one of the hard-to-chamber fired R-P cases. Then put it in your chamber.
Assuming you can close the bolt on it, the ink will rub off on the areas that are sticking.
I suspect you've got excess expansion down in the web area, but it is also common for this to happen right below the sidewall-shoulder junction.
Are you full-length sizing your cases? If not, that's the first step, but tell us where the cases are sticking first.
To "bump" the shoulder you simply need a full-length or body die and appropriate shell-holder. You screw the die down a little at a time until you start to move the shoulder back. Normallly not much of a change is required, just .001-.002". A very simple way to set the amount of bump is to take a .45 acp case. Remove the primer and make sure it is round and trimmed square. Use this with a set of calipers and a fired case. The .45 acp case slips over the neck and stops on the shoulder. Put the base of your 20BR fired case,primer must be removed), on one jaw of the caliper, and the base of the 45acp case on the other jaw. Write down the distance. Now put the case in the FL or body die and work it down in increments. See if you can get it so you see about 0.0015 of shoulder push back.
Of course, if you go too far with a case, you'll need to start again with another fired case,remove the primer first--but don't size the case when you do so). The reason for removing the primer is that the little crater can throw off your precise measuring. The base of the case needs to seat squarely on the caliper jaw. With a primer in place, it may rock.
The need to bump the shoulder may be there, but you really need to find out why your cases are hard to chamber first. I suggest you get a magic marker, and cover the body of one of the hard-to-chamber fired R-P cases. Then put it in your chamber.
Assuming you can close the bolt on it, the ink will rub off on the areas that are sticking.
I suspect you've got excess expansion down in the web area, but it is also common for this to happen right below the sidewall-shoulder junction.
Are you full-length sizing your cases? If not, that's the first step, but tell us where the cases are sticking first.
To "bump" the shoulder you simply need a full-length or body die and appropriate shell-holder. You screw the die down a little at a time until you start to move the shoulder back. Normallly not much of a change is required, just .001-.002". A very simple way to set the amount of bump is to take a .45 acp case. Remove the primer and make sure it is round and trimmed square. Use this with a set of calipers and a fired case. The .45 acp case slips over the neck and stops on the shoulder. Put the base of your 20BR fired case,primer must be removed), on one jaw of the caliper, and the base of the 45acp case on the other jaw. Write down the distance. Now put the case in the FL or body die and work it down in increments. See if you can get it so you see about 0.0015 of shoulder push back.
Of course, if you go too far with a case, you'll need to start again with another fired case,remove the primer first--but don't size the case when you do so). The reason for removing the primer is that the little crater can throw off your precise measuring. The base of the case needs to seat squarely on the caliper jaw. With a primer in place, it may rock.
I am full length resizing. I will try the magic marker trick here in the next day or so and post my results.
Thanks
Thanks
did the marker trick, definately the sholder needs bumped back, but I can't get my die adjusted to do so?
The best and easiest solution is to take those Remington cases and throw them away. Just use the Lapua casees. If you need more then spend the money and buy some more Lapua cases. It sounds like your rifle was chambered for these cases anyway. Seriously, those Remington cases aren't worth the effort. Besides, most likely the rifle will shoot differently between the two types of cases. Do you want to have to develop two different loads for the two different cases? Toss them.
BTW, is the neck size marked on your barrel?
BTW, is the neck size marked on your barrel?
If you have the die screwed flush to your shellholder, and it does not move the shoulder back enough, then you have two choices. First, buy an extra shellholder and have it thined by .002". Second choice is to buy a set of shellholders that are different thicknesses. I cannot remember who sells them, but I know they exsist.
Art
Art
What do you guys think I will get for barrel life out of this 20 BR??? I am shooting right over 4000 fps...Shillen barrel?
Forum Boss
Administrator
ArtD said:
Art is correct that you'll need to reduce the shell-holder to shoulder distance. However, before you start filing the bottom of the die, try screwing the die in farther.
But, you may say, "when the ram is raised, I screw the die all the way down, I can't go any further". Well, lower the ram a bit, and try screwing the die further down in 1/8 turn increments, while checking a lubed case for shoulder movement. I had a turret press that required me to go 1/3 turn past contact to take the "slop" out of the system and create "cam-over". Without that I had the same problem of no shoulder movement.
Interestingly, when I moved the SAME die to a rockchucker, I could get .0015" shoulder bump and the bottom of the die wasn't even touching the shell-holder. Lesson learned? Your bump setting will vary with different presses,and shell-holders too.)
What kind of barrel life can you expect from the 20 calibers??
I do not have experience with a 20BR though I have two PT&G 20BR reamers and am waiting for the Bartlein barrels. The .204Ruger does not seem to be hard on barrels and I do have experience with that caliber, myself and other PD shooters. My guess is that more powder = less barrel life with the 20BR but I doubt if a 39gr Blitzking running 4000fps or so with an additional 3-5grains powder,in the 20BR) would be a barrel burner.
If you were going to order a couple Pac-Nor 3 groove barrels to chamber in 20BR, would you get the traditional or polygonal rifling? Why? Thanks!
If you were going to order a couple Pac-Nor 3 groove barrels to chamber in 20BR, would you get the traditional or polygonal rifling? Why? Thanks!
I only have experience with the traditional, but my luck with this caliber with traditional rifling has been excellent. My gun accuracy has been exceptional with this gun and I have no complaint. If you need any loading data or anything let me know...glad to help with anything I can.
Finally got the 20 BR out in the fields up here in PA. Winter is finally breaking, and on a few nice days here the groundhogs were out. Killed my first two with the gun since I got it. 200 yards and 350 Yards. VERY impressed with the sierra 39 grainer opened them completely up. Five shot groups at 100 yards have been ranging from 0.175 to .402 of a inch. I appreciate everyone who has offered advice on this post, its all paying off!
thanks
Brandon
thanks
Brandon
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