couple of questions for the seasoned benchrest reloaders

C

canuck

Guest
1) what is the best tool to get to measure headsapace for the purposes of loading( to measure the cartridge)

The second question relates to a problem I am having regarding the chambers( or I should say reloading for those chambers).

I got into precesion shooting a few years ago just for the fun of it( no competition for me but maybe down the road). I had a few custom guns built with custom chambers.Both where done with PTG reamers. The first is a 6x47 Lapua with a 0.269 neck. The second is a 7mm rem ulra mag with a 0.317 neck. Of course I have to neck turn for both.
The problem I am having with the 6x47 is after 3 firings I have to use my body die( no big deal and probably should be doing it every time, right?) I take my time and little by little adjusted the die down and size it until it will just fit in the chamber.All sounds good right? However when I go to the range and fire those loads I get stiff bolt lift. I think what is happening is the chamber is small and so by the time I slowly adjust the die down enough to size the body it is creating excess headspace. What do you guys think?
The 7mm ultra mag has a very similar problem but I lose primer pockets by the second load . There are no ejector marks, brass dimensions seem to stay tight.My load would seem light by other's standards but I realize all chambers are different.It has to be pressure causing the lose primer pockets but the load would already seem enemic.No matter how I size them the brass is toast by the 3rd load.
I am thinking I may need a custom die for both of these rifles. I don't want to touch the chambers as they are so bloody accurate.
What are your thoughts?
 
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What is the best tool to get to measure headspace for the purposes of loading (to measure the cartridge)

I've tried different ones over the years, and this Digital Headspace Gauge is hands down, a head above the rest. It extremely easy to use and there's No Hand Strength Differential to worry about [second item down on this page]: http://www.larrywillis.com/ :cool:

P.S. Make sure you punch the primer out of the fired case before you set it down and zero out the reading. F/L size, then take another reading. Once you've set your die to give you the .001" goal you're looking for, QC after 25 cases to ensure nothing has changed. QC-ing once in awhile is always a good habit to get in to. :)
 
I like my old Stoney Point setup, that is now sold by Hornady and a headspace gauge, which of course it is not. If you are blowing out primers after two loadings, your loads are too hot, period. Different barrels produce different amounts of pressure, as do different throat configurations, and seating depths. You need to change something so that you get a more reasonable case life. Listen to your rifle, and believe what it tells you, instead of trying to superimpose your expectations on it. On the 6.5, about how much does your body die reduce fired cases about .3 up from the head, and at the shoulder?
 
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I like my old Stoney Point setup, that is now sold by Hornady and a headspace gauge, which of course it is not. If you are blowing out primers after too loadings, your loads are too hot, period. Different barrels produce different amounts of pressure, as do different throat configurations, and seating depths. You need to change something so that you get a more reasonable case life. Listen to your rifle, and believe what it tells you, instead of trying to superimpose your expectations on it. On the 6.5, about how much does your body die reduce fired cases about .3 up from the head, and at the shoulder?

What you're saying makes sense. I haven't measured the 6x47 cases or even coloured an empty case before sizing. I just thought I would bounce it off you guys here to maybe point me in the right direction.
Thanks for the advice....
 
The second question relates to a problem I am having regarding the chambers( or I should say reloading for those chambers).

I got into precesion shooting a few years ago just for the fun of it( no competition for me but maybe down the road). I had a few custom guns built with custom chambers....

I'm not going to get into this again -- there are two threads simultaneously going on, one called "Head Space" and the other "Fireform or not..." (or words to that effect), and while there is good information in them, there is also a fair bit of BS & outright error. But you could read them...

Here's a different kind of answer: When you have a gunsmith make you a custom chamber, pick one who also offers custom dies as a part of the job. Then take him (her) up on it. They will run $200 or so -- I guess I'm in 1990s pricing mode -- but worth it.

Remember too that the cost of changing to a new chambering should include the cost of new dies. Something that took a while to sink into my head.

If you get into custom chambers, think seriously about getting your own chambering reamer, AND your own resize reamer. With this kind of effort, I'd probably start with the brass to be used when drawing up the reamer specifications. For example, in a number of cases, RWS and Lapua will be .0025 different in diameter at the base. That's about half the difference one normally specifies between a chambering and resize reamer.

Alternatively, there are a few people who can use your chambering reamer to make a FL die -- Jim Carstensen for one -- but it isn't simple. Making custom dies from fired cases is hard -- how does one know just how hard the case(s) was hit before being sent off as "examples"?

Of course you can go halfway to "precision." Which is what generates all these threads...
 
Is the difference between a chambering reamer and resizing reamer about 2-3 thou smaller for the resize?
I actually own the reamers but PTG did not make them how I had asked. I did ask for the neck dimensions( and got that) but specified I did not want an undersized body but I think that is infact what I got.
 
Is the difference between a chambering reamer and resizing reamer about 2-3 thou smaller for the resize?

I said *about half* -- but you can get into a discussion over what the right numbers are. I've never seen anyone say less than .0025; .003 to .004 would be the usual answer given.

You may or may not have an undersized (diameter) body. A chamber cast will settle that. But you often can't easily make a chamber cast to determine how far the reamer was run in.

However, as you do have a chambering reamer, you might well want to consider having Jim Carstensen (JLC Precision) make you a custom FL die. You can also have a headspace gauge made using your reamer -- you just run it into a barrel stub a bit, enough to have the neck & all the shoulder, but not much body, then face off the "neck" end square. Maybe Jim could make that up when he does the die, or if you elect not to go that route, any smith can make the gauge pretty quickly. (Edit) Though a custom gauge could run more than the Stony Point Boyd mentions. One-off work is almost always more costly than mass produced. And may well not be an advantage in this particular situation.
 
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Here's a gauge that I make for this purpose. It's fast, accurate and easy. Notice the indicator stem is offset to not be affected by the primer. Just drop the case in, mouth first and set the indicator top on the base.
023.jpg
[/URL][/IMG]
 
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1)The problem I am having with the 6x47 is after 3 firings I have to use my body die (no big deal and probably should be doing it every time, right?) I take my time and little by little adjusted the die down and size it until it will just fit in the chamber. All sounds good right? However when I go to the range and fire those loads I get stiff bolt lift. I think what is happening is the chamber is small and so by the time I slowly adjust the die down enough to size the body it is creating excess headspace. What do you guys think?

1. Time to learn to Full Length Size each and every time you REload.

2. It might be time to throw that brass away.

"If the action bolt is clicking or popping at the top of the bolt lift, it indicates that the brass is too big near the base. Once you start getting this, you might as well throw the brass in the garbage, as it will be impossible to stop when using full power loads."

"If the bolt closes and opens hard throughout the whole stroke without the pop at the top, this indicates the shoulder needs to be pushed back." - Jim Carstensen

Read the entire article: http://www.accurateshooter.com/technical-articles/full-length-bushing-dies-and-die-conversions/ Good stuff! :)
 
Mike do you have a website...

Here's a gauge that I make for this purpose. It's fast, accurate and easy. Notice the indicator stem is offset to not be affected by the primer. Just drop the case in, mouth first and set the indicator top on the base.
023.jpg
[/URL][/IMG]

with info on this gauge?

Jim
 
...The problem I am having with the 6x47 is after 3 firings I have to use my body die( no big deal and probably should be doing it every time, right?) I take my time and little by little adjusted the die down and size it until it will just fit in the chamber.All sounds good right? However when I go to the range and fire those loads I get stiff bolt lift. I think what is happening is the chamber is small and so by the time I slowly adjust the die down enough to size the body it is creating excess headspace. What do you guys think?...

Here is a procedure that will let you independently adjust base resizing and shoulder bumping:

Additional purchases are (1) a cheap FL die (maybe), and a Lee collet die - or any neck die. Here it is.

1. Get a cheap .308 Winchester FL die. The .308 has a base diameter of .4709, and should let you resize the base of your 6.5x47 Lapua without touching anywhere else. But check the dimensions before buying, if, by the book & reamer print, that's too big, you'll need a 6.5x47 FL die, and need to have it cut off about 1 inch up from the base. Now it will resize the base of a case, whilst touching nothing else.

2. Neck size the new case, seat a bullet, then fire.

3. Drive out the primer, and measure the headspace with the Stony Point (now Hornady?) gauge.

4. Run the case through your makeshift base die.

5. If it still chambers easily, neck size it, seat a bullet, and fire again.

Repeat 2-5 until it won't chamber easily. Since the base has just been resized, it must need shoulder set-back (i.e., headspacing). As soon as the case won't camber easily, measure it with the recently purchased Stoney Point. Set your 6.5x47 FL die so the headspace is moved back between .001 and .002, whatever it takes to "stick" at .001 or a bit more.

With the press ram fully up, with a case in the die, screw down the lock ring, and lock it. Take the die out, re-seat it in the press, and run another case through, to check that you've set the lock ring correctly. Repeat this sequence until you can take the FL die out, reposition it, and get the desired reading.

Your FL die is now properly set for your chamber head clearance, assuming the same press and shell holder. That portion of the chamber is not subject to wear, you are set for the life of that barrel.

Now with your 6.5x47 FL set up to headspace correctly, use it only, and see if your base is sized enough.

I mention this, because the problem you report could - and likely does - come from too hot a load. As several folks pointed out, each barrel/chamber is a bit of an individual.

A second, but less likely situation is that the new Lapua brass has a diameter larger than, say, .003 smaller than your chamber. With hot loads, brass seems to have a memory, and regardless of what the books say, will tend to return to that dimension. That could explain hard bolt lift with warm but "safe" loads. That's a kind of brass-chamber mismatch that is hard to correct. As it is less likely, let's not get into it unless it in fact proves to be what's going on.
 
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with info on this gauge?

Jim

Jim, I've got a fellow shooter putting a website together right now. It'll be a little while before it's done though. Feel free to give me a call if you want. I should be able to answer any questions you may have about it. --Mike 270-542-6022
 
1) what is the best tool to get to measure headsapace for the purposes of loading( to measure the cartridge)

The second question relates to a problem I am having regarding the chambers( or I should say reloading for those chambers).

I got into precesion shooting a few years ago just for the fun of it( no competition for me but maybe down the road). I had a few custom guns built with custom chambers.Both where done with PTG reamers. The first is a 6x47 Lapua with a 0.269 neck. The second is a 7mm rem ulra mag with a 0.317 neck. Of course I have to neck turn for both.
The problem I am having with the 6x47 is after 3 firings I have to use my body die( no big deal and probably should be doing it every time, right?) I take my time and little by little adjusted the die down and size it until it will just fit in the chamber.All sounds good right? However when I go to the range and fire those loads I get stiff bolt lift. I think what is happening is the chamber is small and so by the time I slowly adjust the die down enough to size the body it is creating excess headspace. What do you guys think?
The 7mm ultra mag has a very similar problem but I lose primer pockets by the second load . There are no ejector marks, brass dimensions seem to stay tight.My load would seem light by other's standards but I realize all chambers are different.It has to be pressure causing the lose primer pockets but the load would already seem enemic.No matter how I size them the brass is toast by the 3rd load.
I am thinking I may need a custom die for both of these rifles. I don't want to touch the chambers as they are so bloody accurate.
What are your thoughts?

These are my opinions, I am NOT a seasoned Benchrest competitor and as you will see I disagree with many seasoned shooters.


The best device for measuring shoulder setback is a small stub of short-chambered barrel sometimes called a gizzie which is made by your gunsmith using your chambering reamer.

Body dies are a poor fix for a problem that shouldn't exist.

No gunsmith that I'm aware of will make you good custom FL dies in anything but PPC

Your chambers are too small, a situation so common I'll call it "normal." (I'm completely ABNORMAL as I order my reamers hugely over-sized from SAAMI) And were this my rifle I would hog out the chamber. I have paid to have several opened up, even paid to have them re-chambered because they were too small...... I don't "blame" anyone for this nor ask for favors, I've paid dearly for my mis-informed choices.

I buy a die reamer along with my chambering reamer. Actually NOT a "die reamer" per se but an entirely set up piloted REAMER to go along with my chambering reamer. I will never again buy an un-piloted or "solid pilot" reamer. I have personal opinions regarding taper and sizing effect and have die reamers from .0015 to .004 under on various dimensions and I now order them with a different taper than my chambering reamer.

hth

al
 
It's great that you guys take the time to help rookies like me. Thanks for all the useful tips...I will let you know how it goes. If there are any other ideas I am all ears...
I know what some of you guys are saying about loads but I guess I was looking or hoping for some other kinda fix. If you saw these things shoot I think you would understand why.My best group to date at 109 yards with the 6x47 is 0.081 for 5 shots( but more typically in the 0.1s and 0.2s, sometimes bigger if I screw up . I have also had a number of sub 1 inch 5 shot groups at 500 yards with this same load( but more typically around 1.5 to 2 inches). It is 39 grains of H4350 with a berger 108BT 50 thou off hard engrave. Now, believe it or not the 7mm ultra mag with vais muzzle break is crazy accurate as well but I will defintiely try a lighter load and see what happens.My current load is 88 grains of RL25 with a 162 Amax 30 thou off the lands.I have had some pretty amazing groups with this at ranges out to 1000 yards.
 
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That is a wealth of information inwhich I will need a few days or week to go over and digest.
Ok Al
I am going to put you on the spot.
If you were in my shoes what would you do? Just wait till you shoot the barrel out and start with another reamer?
 
It's great that you guys take the time to help rookies like me. Thanks for all the useful tips...I will let you know how it goes. If there are any other ideas I am all ears...

My best group to date at 109 yards with the 6x47 is 0.081 for 5 shots (but more typically in the 0.1s and 0.2s, sometimes bigger if I screw up.

Actually, we have nothing for you, I'd think. Your groups would win any short range match you entered, except your rifle is likely not quite legal for short-range BR.

As for your long range performance: (1,000 yards; 600 isn't really "long" range) not quite enough info on your current groups. I've been at 1K benchrest 17 years and managed to get the IBS jacket, so if not a great shooter, at least a plug-along determined one...

Don't know what your "amazing groups are a 1K. The number of people who have a group under 4.000 inches (that's the 10-shot matchs) is real small. 100s are pretty rare, too. While close, I'm not a memeber of that select group.
 
If you were in my shoes what would you do? Just wait till you shoot the barrel out and start with another reamer?

For what it's worth, among all the other ideas presented.

When I decided to shoot the 30BR, I had a competent gunsmith [stevensaccuracy.com] build me a rifle. I called Dave Kiff at Pacific Tool and Gauge and purchased the Robinette reamer [$138]. Sent the reamer to Billy Stevens who chambered the barrel and subsequent others. Same chamber all the time. He sends the reamer and barrel back to me when he's done.

Sent three pieces of thrice fired brass to Harrell's for a full length bushing die [$75]. Purchased a Wilson seater die. Purchased a Digital Headspace Gauge from InnovativeTechnologies.com.

I use the F/L sizing die, the Wilson seater and headspace gauge each and every time I reload. It goes like clockwork with nary a hitch. Have never found the need to cut anything off, or use this or that, half of a die, for this or that.

It's just a boring process of checking for a .001" movement of shoulder, confirming, and then moving on with the completion of F/L sizing and bullet seating for perfectly matched rounds every time.

Again, for what it's worth. :)
 
Actually, we have nothing for you, I'd think. Your groups would win any short range match you entered, except your rifle is likely not quite legal for short-range BR.

As for your long range performance: (1,000 yards; 600 isn't really "long" range) not quite enough info on your current groups. I've been at 1K benchrest 17 years and managed to get the IBS jacket, so if not a great shooter, at least a plug-along determined one...

Don't know what your "amazing groups are a 1K. The number of people who have a group under 4.000 inches (that's the 10-shot matchs) is real small. 100s are pretty rare, too. While close, I'm not a memeber of that select group.

I really don't think I would be consistent enough to win any match. I have only ever shot good groups with very little to no wind Yes, I have had some really good groups when the conditions were perfect or near perfect( but I didn't tell you about the bad ones even in perfect conditions. It takes consistency to win and pulling a few groups in the 0.4s would eliminate any chance I would think( I was a top level archer at one time so I know what it takes and I do not possess those skills with a rifle,period). Add wind to the equation and my group size would go up considerably . Infact to be honest I avoid shooting on windy days cause I simply get too frustrated. I imagine it would take years and a good system of recording to master that skill.
Perhaps I shouldn't have mentioned anything about groups. I was only doing so to demonstrate why I was so hesitant to mess with the gun and loads. If I gave the impression that I shoot like this all the time let me set the record straight right now and say this is not the case.
 
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]...( I was a top level archer at one time so I know what it takes and I do not possess those skills with a rifle, period). Add wind to the equation and my group size would go up considerably . In fact to be honest I avoid shooting on windy days cause I simply get too frustrated.

So shoot a few matches. The wind's the same for everyone, and as soon as you learn most people can't read it either (match shooting will teach you that), you *should* get less frustrated. The wind blows an arrow, too.

On that note, a long time ago, Gary Anderson (Olympic .22 rimfire Gold Medalist) once went to a benchrest match. He borrowed a rifle, and set a new aggregate (not group) record. This because he could transfer knowledge of how wind direction (percent of cross-wind deflection when quartering, etc.) affected a bullet with the much smaller-moving CF bullets. It probably took him a bit & a few sighters, but the principle's the same.

As with an arrow.

If you stay on the internet, you'll just get scared. In your particular case, competition might be soothing.

Edit:

And on that note, a load that gives you an occasional real small group & the rest big is not a good load. As a guess only -- your loads are a bit too hot in your rifle. Backing them off shouldn't hurt much. If it does, and if (big if) you don't get big ones with those case-destroying loads, well, while surely not recommending it (safety reasons), I'll allow I do know some record-setting shooters at 1K who don't have very good case life...:eek:

Now some more tooling to restore primer pockets for another couple loads ... ah, no. Not on the internet.

 
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