OAL vs. Accuracy

I understand that for some of you guys the groupings I'm getting now are acceptable hunting loads. They certainly are within the kill zone, at least at 100-200 yds. I strive to get that 3-leaf clover target with all my hunting loads, and have had that type of success for my 22-250 and 270. Those loads seemed to develop easily, research, try a few powders and bullets, there's the sweet spot and then fine tune.

This 30-06 seems to be a bit more challenging. So I am going to do up a dummy round out to the Lyman book spec's which I believe is 3.34", felt-tip the bullet and see where it sits to the lands/grooves. I will back off or not, depending upon the results and then adjust from there.

And perhaps I'm over reacting/researching. The 22-250 and 270 loads were my initial jump into reloading and I felt quite successful early on with the results. Go to the Lyman book, max length, see if it fits the rifle (if not, reduce the OAL) until it fit, load and shoot.

It's interesting how adjusting the OAL didn't provide tighter groups. However, in fairness, I didn't have an opportunity to shoot that last 3 reducing lengths due to weather, hope to get over that hump this coming weekend.
 
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Total OAL To Lands

Internet, books, mag's, I read that one way to determine OAL to lands is to take the bullet and slowly slide it into the rifling, then take an empty fired cartridge and with the rifle at a downward angle, slowly move the bolt until the cartridge touches the rifling. Once this is accomplished, take a cleaning rod, insert from the crown end of the barrel until it touches the bullet...measure this length. Next, remove all, close the bolt and take a 2nd measure. The difference will be the OAL touching the lands. Now back off 1/10 or 1/100. Has anyone tried this?
 
waynewjw said:
Internet, books, mag's, I read that one way to determine OAL to lands is to take the bullet and slowly slide it into the rifling, then take an empty fired cartridge and with the rifle at a downward angle, slowly move the bolt until the cartridge touches the rifling. Once this is accomplished, take a cleaning rod, insert from the crown end of the barrel until it touches the bullet...measure this length. Next, remove all, close the bolt and take a 2nd measure. The difference will be the OAL touching the lands. Now back off 1/10 or 1/100. Has anyone tried this?
Click to expand...

I don't think that what you described is accurate way to determine COL.
First of all if you using cleaning rod or dowel this way your COL will vary as per tip of bullet deformation.
If you use empty fired casing.. bullet will drop inside the case....

I use neck sized, deprimed case and lubricate bullet shank slightly than will start bullet in seating die, than it is jammed in to rifling using bolt.

I don't see need for using marker or candle as I can see rifling marks on the jacket.

Once I have dummy round I am using digital head space gauge from

www.larrywillis.com/ measuring seating depth from ogive, not from tip.

Some use Hornady bullet comparator or one could cut piece of tube that internal diameter would rest on ogive and use this just the same.

Mystic precision (sponsor) has good info on his site and he uses COL to fit magazine and than varies powder charges to fine tune load.
I will try this method and see how it works for me, but it seems to be easier than playing with seating depth.

He says that you have to have very accurate scale capable to measure 0.1 grains.
From my observation loading IMR 4350 powder 0.1 gr equals 2 kernels of this powder, so it would be relatively easy and accurate to test fire loads
that differ by 0.1 gr. or 2 kernels.

Andrew
 
All Things Being Equal

My RCBS Chargemaster Combo handles 0.1 gn increments very well. So if one measures a few bullets to determine they are all equal and then insert a fired cartridge, with metal rod at crown, measurement would be accurate. Empty chamber, closed bolt, measured to the bolt, minus 1st measure would provide OAL. 3 or 4 bullets should provide an "average" starting point?
 
Everyone has given some good advice. I will throw one out there too... Get yourself a Hornady OAL gauge and a set of comparators and never look back. My 300wsm shoots 1" @100 yards and 2" @200 yards 30thou from the lands. I tried to better that and learned the expensive way that 1" was plenty for moose. Now my .223 HB Remington has a sweet spot of 22thou off the lands and shoots one ragged hole @100yrds and 20 thou from the lands wasn't as good. With the difference found in some bullet tips 22 thou would not be achievable unless measured from the ogive. I started 30thou for my 223 and found a powder charge that gave consistant speed per round and then played the OAL game to tighten groups. Good Luck.....all in all shooting is the fun part.
 
Without Gauge

I was hoping to do this the simple way, bullet in barrel, without purchasing the gauge and other stuff. Otherwise, I'm going to be buying more "stuff" and I don't need to buy more "stuff".

Anyway, I'm off to my reloading room shortly, will marker the bullet and go for max. OAL and then develop from there.
 
In all my factory barreled rifles I have normally made a dummy cartridge by chambering a loosely seated bullet and closing the bolt and using that for OAL. I have one rifle with a Shilen barrel and doing that made the groups terrible and the SAAMI spec OAL has shot the best.
 
For a hunting rifle, I would start with the bullet about 30 thou off the lands and try a medley of longer loads in 5 thou increments, to see if the rifle had a strong preference, before I tried different powder charges.

Keep in mind that the bullets vary in ogive length from bullet to bullet and lot to lot, so using a load close to the lands is not good unless you have a bunch of the bullets from the same lot number.
 
You Mean???

Ganderite said:
For a hunting rifle, I would start with the bullet about 30 thou off the lands and try a medley of longer loads in 5 thou increments, to see if the rifle had a strong preference, before I tried different powder charges.

Keep in mind that the bullets vary in ogive length from bullet to bullet and lot to lot, so using a load close to the lands is not good unless you have a bunch of the bullets from the same lot number.
Click to expand...

You mean 30 thou off the lands, then decrease each successive length by 5 thousands? That's pretty small decrease per each, I would think the bullets need to be pretty consistent same length.
 
Since all old timers on here are usually referred to as Fudds, I'll explain, which is probably the best and easiest way, to see how far your particular bullets are seated from the lands, which was the way the Fudds did it, years ago.
You should have a wooden dowel that goes through your barrel, it is much easier to use than a cleaning rod.
Take the bolt out of your rifle, if it has a removable bolt. Take one of the bullets you are using. Drop it into the chammber, nose first. Take a pencil and push the bullet tight against the lands. While holding it there, put your dowel down the barrel until it touches the bullet you are holding in. Then make a neat mark on the dowel, with a sharp pencil, at the end of the barrel.
Remove the bullet and place a loaded cartridge in the chamber. With your fingers, make sure it is fully seated, then hold it there. Push your dowel in until it touches the bullet. make another mark on the dowel. The distance between the two marks is the distance your loaded bullet is from the lands.
 
Another Method

H4831 said:
Since all old timers on here are usually referred to as Fudds, I'll explain, which is probably the best and easiest way, to see how far your particular bullets are seated from the lands, which was the way the Fudds did it, years ago.
You should have a wooden dowel that goes through your barrel, it is much easier to use than a cleaning rod.
Take the bolt out of your rifle, if it has a removable bolt. Take one of the bullets you are using. Drop it into the chammber, nose first. Take a pencil and push the bullet tight against the lands. While holding it there, put your dowel down the barrel until it touches the bullet you are holding in. Then make a neat mark on the dowel, with a sharp pencil, at the end of the barrel.
Remove the bullet and place a loaded cartridge in the chamber. With your fingers, make sure it is fully seated, then hold it there. Push your dowel in until it touches the bullet. make another mark on the dowel. The distance between the two marks is the distance your loaded bullet is from the lands.
Click to expand...

Hey H, I understand, but if there is no difference between the two, I'm thinking I'm no closer to determining ideal OAL. So, will this work the same?

Bullet in barrel as above, dowel in barrel and mark it. Remove bullet, close bolt on empty chamber, dowel in barrel touching the bolt and mark it. Now I have an OAL with bullet touching the lands. Back off say 30/1000ths and see if bullet is marked by lands. If no marks, this is starting OAL???
 
waynewjw said:
Hey H, I understand, but if there is no difference between the two, I'm thinking I'm no closer to determining ideal OAL. So, will this work the same?

Bullet in barrel as above, dowel in barrel and mark it. Remove bullet, close bolt on empty chamber, dowel in barrel touching the bolt and mark it. Now I have an OAL with bullet touching the lands. Back off say 30/1000ths and see if bullet is marked by lands. If no marks, this is starting OAL???
Click to expand...

I can't see any advantage in that version.
Quit worrying about marks of the lands on the bullet.
Just do it as I said. If the marks on the dowel are the same, your loaded round held in and the bullet only, you are touching the lands. So, back off what ever you want.
If the marks are a fair distance apart, then seat the bullets further out. You can still measure the overall length of the cartridge, if you like, then add how much you want, to bring it to the desired clearance, if any, that you want.
 
Wayne - The above described Fudd method ( I can say that cause I'm old ) is superior to trying to jam an oversize and marked case into the lands. Your suggested modified Fudd approach will work as well - I find that you need to make sure that the rifle is cocked to ensure that the bolt has not slipped forward due to free play.
 
I Got It

So, I'll be picking up a dowel on the way home tonight and checking OAL. Plan to resize existing loads and head to the range tomorrow for some 30-06 shooting. Will report results back once completed.

Thanks for all the info about OAL. Sounds simple and straight forward but not so much once you start tinkering around with different rifles and different bullets for the same rifle.
 
It's also nice to have a dowel on hand in case you ever get a patch stuck in the barrel. I use a Patch Worm and have had a couple come off the end before.
 
H4831 said:
Since all old timers on here are usually referred to as Fudds, I'll explain, which is probably the best and easiest way, to see how far your particular bullets are seated from the lands, which was the way the Fudds did it, years ago.
You should have a wooden dowel that goes through your barrel, it is much easier to use than a cleaning rod.
Take the bolt out of your rifle, if it has a removable bolt. Take one of the bullets you are using. Drop it into the chammber, nose first. Take a pencil and push the bullet tight against the lands. While holding it there, put your dowel down the barrel until it touches the bullet you are holding in. Then make a neat mark on the dowel, with a sharp pencil, at the end of the barrel.
Remove the bullet and place a loaded cartridge in the chamber. With your fingers, make sure it is fully seated, then hold it there. Push your dowel in until it touches the bullet. make another mark on the dowel. The distance between the two marks is the distance your loaded bullet is from the lands.
Click to expand...

This is great advice. I am old and I forgot about this method thanks.
 
cosmic said:
Wayne - The above described Fudd method ( I can say that cause I'm old ) is superior to trying to jam an oversize and marked case into the lands. Your suggested modified Fudd approach will work as well - I find that you need to make sure that the rifle is cocked to ensure that the bolt has not slipped forward due to free play.
Click to expand...

You need to have the rifle cocked or you will be measureing to the tip of the fireing pin instead of the boltface.

I use a slight variation, useing a small collection of various sized drill-rod picked up for the purpose and a pack of drill-bit stop collars that I got out a bargain bin for a buck once. The rest is the same except I can measure between two locked down collars with a caliper instead of guestimateing tape, pencil marks or chainsaw cuts on a willow stick. Cleaning rods don't work that well, as a quick examination of all my rods reveal threaded holes in the end for the bullet tips to hit and all the jags have points that slip past bullet tips and randomly hit the fireing pin hole.

Something to watch for is that simplely dropping the bullet down into the throat will usually jam it 30 thousandths. The dented case mouth on a fired case usually gives about 30 thou jam as well. Sometimes I wonder if thats where the age old "back off 30" advice comes from? Useing the rod technique allows finding the slightest contact if you feel for it. On a related note, its supriseing how far one can jam a bullet with a Stoney Point tool.

When the measurements are done, the calculated COL still only applies to the specific bullet that you did the measurements with. That's OK if you use that particular bullet to set your seating die. You can also measure the completed cartridge on a comparator to have a number to use with other bullets.
 
H4831 be carefull when using the term fudd, there is a difference between old fart and fudd, kind of like mixing up clip and mag. :D These terms are not interchangeable in my old fart opinion.cou:
 
dead meat said:
H4831 be carefull when using the term fudd, there is a difference between old fart and fudd, kind of like mixing up clip and mag. :D These terms are not interchangeable in my old fart opinion.cou:
Click to expand...

I read you loud and clear. However, this was my remark about Fudds.
"Since all old timers on here are usually referred to as Fudds"
Unfortuneatly, there are a lot on here who consider us as Fudds, just because of our age.
I really couldn't care less.
 
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