Stacking tolerances - at the reload bench thru the target

[Webster]

No different than any other person on here, I like to build and shoot small groups.

There have been, untold number of posts about different steps to take, and, and, and......


Take a step back and consider........

For the most part, ALL of the reloading equipment we are using, is, nothing short of bulk production. Presses, shell holders, dies, brass, bullets, primers.

IF using shell holders, at the minimum, there are three different machining planes - base slot - fits in the ram, rim slot - case head fits into, and the depth of the slot for the case head.

Press - ram concentricity with threaded portion for dies (only considering the minimum).

Sizing dies - concentricity of bore, outer threads, bore/outer threads/decapping pin. Body or neck dies are in the same boat.

Brass - mass produced, regardless of brand. Some better, some worse, out of the box. Some "brass" is higher quality raw material.

Bullets - multiple factors.

Action - multiple factors

Barrels - multiple and multiple factors


At the end of the day, because NONE of the above are built with the same reamer, on the same lathe, by the SAME person, is never accomplished.


My point is, watching and reading the variety of posts and answers, most don't ever consider we are damn lucky to push the pointy object and hit a sub moa target with repeatability. To read some of the observations, especially the snarky, makes me shake my head. My favorites "I have been reloading for xx years and this is THE way to do this".

The problem I see is that there are so many replies by average shooters that you cannot sort the good info from the it's just my opinion. I tend to ignore all the replies. If I want good info, I look at what the top shooters in the country do. I keep everything really simple as long as I get good results. I did failure analysis for 45 years so I am pretty good at analyzing problems.

 

[jackieschmidt]

The problem I see is that there are so many replies by average shooters that you cannot sort the good info from the it's just my opinion. I tend to ignore all the replies. If I want good info, I look at what the top shooters in the country do. I keep everything really simple as long as I get good results. I did failure analysis for 45 years so I am pretty good at analyzing problems.

You sparked my curiosity. What was your main field in failure analysis.

I get involved with a certain amount of failure analysis in the Marine Industry where we find causes of failure ranging from poor choice in materials, faulty engineering, poor manufacturing procedures, and just plain ole abuse of equipment.

 

[Dave M.]

Neck tension.

I think you can tune the rifle to either light or heavy neck tension. I’ve personally done both. I have rifles that shoot best with lighter tension and others that shoot best with heavier neck “tension”. There is no specific neck “tension” that will shoot best in all rifles. I think we are saying the same thing here Larry, I just wanted to clarify in case there are some newer shooters or reloaders don’t get the impression there is some magic neck tension that will make their rifle shine.

 

[Dave M.]

Thoughts from an old shooter and what I've learned:

Stacking tolerances - yea, when you consider that it is quite amazing the precision that most firearms achieve even with factory ammo and reloaders like me that just do the basic essentials. However, I believe that the components including factory ammo, is much better than when I got into the sport in the late 60's. Also, some old myths have been dispelled but others have been created in their place.

However, I take a slight issue with your remark about experience. There is value in experience if you learn from it and make intelligent choices and changes. But, also, one should not be afraid to try something new especially if one is trying to address a problem. I agree that just because you have been shooting a long time doesn't mean you know it all if that was your point.

Before embracing a new idea or concept, I believe it is wise to test the assertion before jumping in wholesale. If you use performance on paper as the criteria, it's hard to imagine a better standard to test an assertion. For example, doing XYZ produces an improved ABC but does it show on paper or in other words, can a performance improvement be demonstrated.

While the variation in components and equipment surely are essential factors in precision shooting, the most significant factor (variable) I've learned in 50+ years in the shooting sports is the shooter. I've seen it in competition and in the hunting fields many times.

Also, tiny groups are nice, but I'll take a larger group (within reason) any day that has a more consistent, repeatable point of impact.

While one should never close one's mind to new ideas and methods, I feel a great sense of empathy for new shooters entering the sport with the information overload on the net. All of which is making the sport overly complicated and complex and potentially frustrating to a new shooter thus destroying the enjoyment aspect of the sport. It really isn't that complicated to clean a rifle or reload ammunition to produce a serviceable result for most applications.

This is so true and very well said. Honestly, I test everything. If a certain process doesn’t show an improvement on target (or increase the useful life of competition brass), then I simply stop doing it. Don’t believe any magic solution that will make you a winner until you can prove it for yourself that there is true value in doing it.
Dave

 

[Dave M.]

You sparked my curiosity. What was your main field in failure analysis.

I get involved with a certain amount of failure analysis in the Marine Industry where we find causes of failure ranging from poor choice in materials, faulty engineering, poor manufacturing procedures, and just plain ole abuse of equipment.

And probably a fair amount of galvanic corrosion in marine work I imagine.

 

[M-61]

I’m a short range group shooter. I put a lot of emphasis on ‘practice’.
I don’t mean practice reloading. I mean getting to the range and practicing.
Also there are days I realize it may just not be MY day.

 

[jackieschmidt]

And probably a fair amount of galvanic corrosion in marine work I imagine.

True. Most of our customers run the Intracoastal Waterway System. It is usually best described as brackish, full of all sorts of stuff that seems to eat away at everything.

We take great pains in protecting any surface from the elements, either with Stainless Steel overlay or epoxy resin fiberglass over stainless lap joints.

Here are two of my men applying the Fiberglass Coating on the exposed areas of a new 9” diameter 36 foot long shaft. We put 7 overlapping layers on.

 

[Old Navy]

I think you can tune the rifle to either light or heavy neck tension. I’ve personally done both. I have rifles that shoot best with lighter tension and others that shoot best with heavier neck “tension”. There is no specific neck “tension” that will shoot best in all rifles. I think we are saying the same thing here Larry, I just wanted to clarify in case there are some newer shooters or reloaders don’t get the impression there is some magic neck tension that will make their rifle shine.

Good reply.

 

[Sandstorm]

don’t get the impression there is some magic

You just need to test everything to find your own Magic formula that works for you.
and then repeat. Some days are better than other's and some are Magic.

 

[WVRJ]

I'm old enough to know what it was like back in the late 70's.There was no internet.We had paper books and in every shooting sport I got into,the other shooters were always willing to help me,and I tried to help them.Back then a rifle that was capable of staying in the .3's and 4's was rare.It was hand built and well tuned.Over the years the tools it takes to build rifles,dies,brass and bullets have improved a lot.Never in my wildest dreams back then did I think I would be able to shoot groups that could be covered by a nickel at 300 yards,but now that's pretty fair shooting,but certainly not noteworthy.I have one such group hanging on my office wall that has 3 shots dead center in one oval shaped hole and the other two are out just a little bit.I recently bought a Bergara HMR in 6.5 Creedmoor,and the only thing I had to do to get it under half minute of angle was load it.No tinkering with anything,simply put together some good ammo and clean the bore and shoot it.5 rounds in .435.Next group,5 rounds in .390.Next group in .502.Done with an out of the box production rifle.What a wonderful time to be a shooter!The tools we have now are incredible,and they keep getting better.I have a few very good shooting rifles that I put together using an ancient South Bend lathe that my cousin bought from a guy who had it under a tarp in his garage for 600 bucks.I learned a little bit about it and tried to do a barrel.And it worked,the rifle is one of the better guns in my safe.Yes,a lot of info out there isn't right,but if we read and learn how to separate the brush from the timber,we have a wealth of knowledge and experience at our fingertips.Sometimes guys are spewing BS to stoke their own ego,and these aren't the ones who know their stuff.The ones who go more from real experience are the ones I pay attention to,and I thank them.

 

[acloco]

I'm old enough to know what it was like back in the late 70's.There was no internet.We had paper books and in every shooting sport I got into,the other shooters were always willing to help me,and I tried to help them.Back then a rifle that was capable of staying in the .3's and 4's was rare.It was hand built and well tuned.Over the years the tools it takes to build rifles,dies,brass and bullets have improved a lot.Never in my wildest dreams back then did I think I would be able to shoot groups that could be covered by a nickel at 300 yards,but now that's pretty fair shooting,but certainly not noteworthy.I have one such group hanging on my office wall that has 3 shots dead center in one oval shaped hole and the other two are out just a little bit.I recently bought a Bergara HMR in 6.5 Creedmoor,and the only thing I had to do to get it under half minute of angle was load it.No tinkering with anything,simply put together some good ammo and clean the bore and shoot it.5 rounds in .435.Next group,5 rounds in .390.Next group in .502.Done with an out of the box production rifle.What a wonderful time to be a shooter!The tools we have now are incredible,and they keep getting better.I have a few very good shooting rifles that I put together using an ancient South Bend lathe that my cousin bought from a guy who had it under a tarp in his garage for 600 bucks.I learned a little bit about it and tried to do a barrel.And it worked,the rifle is one of the better guns in my safe.Yes,a lot of info out there isn't right,but if we read and learn how to separate the brush from the timber,we have a wealth of knowledge and experience at our fingertips.Sometimes guys are spewing BS to stoke their own ego,and these aren't the ones who know their stuff.The ones who go more from real experience are the ones I pay attention to,and I thank them.

Optics are sooooo much better now.


My post is about, the topic....stacking tolerances. Believe it is AMAZING that a factory action, with a factory or aftermarket barrel, being fed factory (read "factory" as high volume) or hand loads.

Between the press, shell holder (if utilized), sizing die, seating die, and stuffing into an action, lug, barrel........hence the title.

"Tolerances" is not just square, but 3 and 4 dimensional.

 

[jelenko]

Back then a rifle that was capable of staying in the .3's and 4's was rare.It was hand built and well tuned.Over the years the tools it takes to build rifles,dies,brass and bullets have improved a lot.Never in my wildest dreams back then did I think I would be able to shoot groups that could be covered by a nickel at 300 yards,but now that's pretty fair shooting,but certainly not noteworthy.

Interesting!
I bought my first rifle in 1992 but had no idea how they've improved.

At the same time, aren't factory hunting rifle still a 2" gun at 100 yards?

 

[Sleepyhollow]

As a new short range benchrest shooter less then a year ago I had lots to learn and still learn something new daily. That magical one hole 5 shot group takes alot of little factors to equal up. Here are few things I've learn on my journey.
First there alot of good info on the internet but you gotta learn to weed out the bullshit. You wanna know the truth to something test it yourself. Testing takes alot time and alot of components. But it's it the only way you'll find out what works for you. Don't waste components on a crap barrel. It'll do nothing but piss you off !
Never fire a round without flags !! If you do all your doing is setting yourself up for failure. Knowing when to shoot is key. Learn the wind and how it affects your group. Be consistent with everything from loading to cleaning and keep extensive notes on everything ! Knowledge and bench time is the key to success. If your having issue with something and can't figure it out call someone who been there and donee that.
Learn cause and effect. You don't know til you try. Learn what happens when you get too hot powder. Too long of too short on seating depth. Learning the cause and effect game will make you a better shooter. Most off all have fun and enjoy what your doing.

Happy shooting

 

[Larry Koch]

I think you can tune the rifle to either light or heavy neck tension. I’ve personally done both. I have rifles that shoot best with lighter tension and others that shoot best with heavier neck “tension”. There is no specific neck “tension” that will shoot best in all rifles. I think we are saying the same thing here Larry, I just wanted to clarify in case there are some newer shooters or reloaders don’t get the impression there is some magic neck tension that will make their rifle shine.

Consistent neck tension.

 

[Dave M.]

Consistent neck tension.

That’s the key. Consistency of the neck tension. That’s why I feel properly annealed brass is key. Either that or you have to be 100% diligent that every piece of brass has the same number of firings (and even then brass life is shortened by not ever annealing).
Dave

 

[Ray123]

I own 2 lathes and a Bridgeport mill, so I do all my own rebarreling, buying alot of tooling and support tools like a diamond grinder to go with both is expensive and a lifetime endeavor.
But it's not just building and accurate rifle, that you get to do, you can do all sorts of things or experiments with respect to accuracy or lighting the hunting load. As you tinker, adjust, measure, weigh, turn, etc. with your load development, ...don't leave out the rifle.
Barrel tunner, or muzzle brake of your design, a new barrel crown experiment, longer throat, improved chamber, shorten barrel, barrel contour change, feed longer cartridges, scope rail, ultra light rifle for hunting, fluting, bolt knob design, make your own dies, for forming a cartridge you desire. Machine cartridge cases to exacting standards, same capacity, with no runout, start with straight wall & machine interior, neck down, probably several steps, turn necks id, od, trim to exact length...cases are identical and perfect as possible. But will it improve group size? With all the other variables that you can not control probably not. Powder combustion, and primer ignition are definitely variables, even when weighed can not produce the exact same result, as they are blended materials with a slightly different composition, with atoms of elements out of position in each compared to the next kernel of powder or wildly out of place in a complete mixture in a primer cup.
So sometimes it's just luck, or uncontrolled variables that cancel one another that help or hurt a small group...not even counting the operator, a big variable, sees a one hole group forming and looses concentration. 3 shots, 5 shots, 10 shots, 20 shots, watch the group open. You can only do so much with this outdated gunpowder/lead platform of variables...but it's fun to try. "Keep on Chooglin"... comes to mind. "Have a good time."