Seating rifle bullets

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I'm starting to reload my 243 again & looking to improve accuracy to the maximum potential of my rifle. I have read that seating the bullet out to where the jacket touches the lands improves accuracy so I placed a bullet in a case & locked it in the chamber to see where it stopped.

In my rifle the bullet (Speer 100 grain) touches the lands well before reaching the cannelure. I usually seat so that I crimp at the cannelure (I thought that was what it was for). Is crimping before reaching the cannelure going to be a problem?
 
I'm starting to reload my 243 again & looking to improve accuracy to the maximum potential of my rifle. I have read that seating the bullet out to where the jacket touches the lands improves accuracy so I placed a bullet in a case & locked it in the chamber to see where it stopped.

In my rifle the bullet (Speer 100 grain) touches the lands well before reaching the cannelure. I usually seat so that I crimp at the cannelure (I thought that was what it was for). Is crimping before reaching the cannelure going to be a problem?
You don't have to crimp at all.

Putting the bullet in the case and ramming it into the lands is not a very good practice. Buy a Hornady OAL tool for safer results.

Only problem I can see you running into with the bullet reaching the lands before the case mouth hits the cannelure is the neck tension on the bullet. You want a good amount of the bullet in the case. My buddies Remington 700 is either cut so long or the throats burned out so bad that the bullets actually fall out of the case before touching the lands. My standard savage axis has a very long throat and i cannot reach the lands without over 3/4 of the bullet hanging out of the case.

Not to sound like a jerk here, but sounds like your a new reloader. I suggest getting a manual or two and read them a few times.
 
. . . looking to improve accuracy to the maximum potential of my rifle.
Then don't crimp.

I have read that seating the bullet out to where the jacket touches the lands improves accuracy. . .
It's not that simple, or certain. For sure a consistent jump-to-lands is good, and a short jump is probably good. No (zero) jump is not necessarily good.

I would advise you start at 0.020 jump, and see.
 
Generally best accuracy is "close" to the lands without actually touching. Actually touching can cause problems. I seat the bullets so they will just barely fit the magazine. In most cases they will not hit the lands, but if they do then I seat them a bit deeper. Chances are good that the round you experimented with won't fit the magazine anyway.

From a practical point of view that is as close as I can get unless I want a single shot.

I ignore the cannelure. In fact most bullets I load don't even have them.
 
I see the cannelure as a general suggestion on where to seat

I don’t jam the lands. .020 would be an OK start

I don’t use a regular crimp. I use a Lee collet die
 
As others have said, ignore the grove and do not crimp. To adjust the die body back off the set ring on the seating die body and with an empty case in the press with the ram at the high position slowly run the seating die down into the case until you feel it touch the neck of the case, then back the seating die off a full turn. This will place the crimping portion of the die about .035 above the case. Hold the die firmly so it won't turn and set the lock ring.

To set the seating die stem take a black sharpie and color the front of a seated bullet where the lands will touch. Run a seated bullet with the ojive colored black into the chamber of the rifle and if it does not show slight marks on the bullet back the seating die stem off 1/3 turn and try again with the next seated bullet and keep doing this until the bullet touches the lands. After the touch turn the seating die stem in about 1/3 turn and this will place the front of the bullet about .010 off the lands. One full turn on the stem changes the seating about .035. Hope this helps.
 
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For now I would load a good quality bullet with a repeatable process with a tested OAL and see if that improves accuracy over factory ammo. I'm fairly sure it will. Do some more research and read the front of your loading manual and maybe a book on precision rifle ammo.
Good luck.
 
My load is 33.5 grains of IMR 3031 behind a 100 grain bullet. Crimping at the cannelure I get good but not great results. I think I can do better if I play with the bullet seating a bit. By the way with the bullet seated at the maximum length it fits my magazine & cycles fine. I will try seating it deeper in .010" increments & see what happens. In case this is of any interest or makes any difference my rifle is an old model Ruger Model 77. Thank you all .
 
I'm starting to reload my 243 again & looking to improve accuracy to the maximum potential of my rifle. I have read that seating the bullet out to where the jacket touches the lands improves accuracy so I placed a bullet in a case & locked it in the chamber to see where it stopped.

In my rifle the bullet (Speer 100 grain) touches the lands well before reaching the cannelure. I usually seat so that I crimp at the cannelure (I thought that was what it was for). Is crimping before reaching the cannelure going to be a problem?
Well this is sort of a yes and no thing. How far back to seat a bullet off the lands is just one of those questions which depends on your rifle. We can even really go by rifle model numbers with this but simply put your rifle. I know guys in the bench rest crowd who literally gently start a bullet into a case and then chamber the round so they are literally using a closing bolt to seat their bullets. I doubt you can get a bullet ogive any closer to the lands than that. Then too since we are not all bench rest guys that point of trivia really matters not. :)

My buddies Remington 700 is either cut so long or the throats burned out so bad that the bullets actually fall out of the case before touching the lands.
That really isn't all that unusual in that most of the factory Remington rifles I have been around including my own have a long lead or throat. So I am not surprised by that.

I have also used the method you used to find out where my bullets actually engage the lands and grooves (rifling) in a barrel. I take a sized case (no charge or primer) and gently start to seat a bullet. Then I chamber that round slow and easy. I then carefully extract the round. We don't want to jam with any force the bullet into the rifling as when we extract it we want a good measurement. Then we can load backing our bullet out several thousandths at a time looking for the "sweet spot" which is like looking for the holy grail of sorts.

The downside to all of this is that bullets, even very good well made precision bullets are not always as consistent base to ogive or tip to ogive as we would like them to be. Measure a handful if you aren't sure about that. This is where I give those bench rest guys some credit as when they use a bolt breech face to seat a bullet they know their bullet ogive is without any doubt on the rifling.

When you say "crimping" I am not sure exactly what you mean? Lee sells their FCD (Factory Crimp Die) which uses a collet to squeeze a crimp on a case mouth. Other crimp dies can also work this way. There is the standard what we call taper crimp which places neck tension on a bullet as the bullet is seated. This is common and amounts to an interference fit of bullet into case mouth. This is the most common practice.

If I were you I would start loading 243 Winchester exactly per the load data for the bullet you are using. Just as an example using a Speer 100 grain bullet I would load to a C.O.L. of 2.635" in a case I have resized and trimmed to 2.035". Once you have a load which performs well and gives good tight groups then I would worry anbou experimenting with seating depth. I would slowly start bringing my C.O.L. up in numbers and see what happens. Keep in mind this may or may not have much impact in accuracy on your specific rifle.

Just My Take
Ron
 
Provided your sizing die is good, neck tension is all that's needed to hold the bullet in the case. Disregard cannelure...no crimping necessary as noted above. In addition to the Hornady OAL Gauge, grab a Hornady Modified Case and Hornady Comparator for accurately making the critical ogive-to-base measurement. Don't measure to bullet tip - that's a rookie move. Your magazine may well dictate your max length unless you intend to hand-feed rounds, by-passing the mag, directly into the chamber.
 
My load is 33.5 grains of IMR 3031 behind a 100 grain bullet. Crimping at the cannelure I get good but not great results. I think I can do better if I play with the bullet seating a bit. By the way with the bullet seated at the maximum length it fits my magazine & cycles fine. I will try seating it deeper in .010" increments & see what happens. In case this is of any interest or makes any difference my rifle is an old model Ruger Model 77. Thank you all .
If your seating it deeper I would suggest backing off the load a bit. I noticed with some of my big bore rifles that crimp effected groups. I quit crimping 44mag in my single shot because it went from 4'' groups to 2'' groups.
 
With my Howa 1500 30-06 while working up a load I found 2, after that I tried OAL changes with both, one didn't matter and the other was about 1/4" difference. With the Rem 700 it shoots better with longer seated 168gr bullets that I crimp with the Lee FCD, I've never tried it not crimped
 
I could seat a 100 gr rn (and yes I still have some) to 2.73 and still not hit the lands in my rem, but I seat a 100 gr sp (not spbt) to 2.65 and with a max load of h1000, I'll get a fly ready for beach season. In my supershorthroatedsavage, it's a 95 gr btip that shoots gorgeous with a max load of h1000 at 2.63. Neither bullet has ever suffer the tragedy of crimping. In an ar10 I MIGHT crimp, but I'd test 20-50 rds to be sure they NEEDED it.
 
Firstly ‘
No one on this forum or any other can tell you what the best seating depth is for your rifle. You must test for yourself.

Secondly,Seating depth will have a huge effect on accuracy.

Thirdly, if you’re restricted to magazine length ammunition you may never reach your rifles potential, this may not be a problem for tactical or hunting applications.
Fourthly, and to address the original question, don’t crimp
J
 
I'm starting to reload my 243 again & looking to improve accuracy to the maximum potential of my rifle. I have read that seating the bullet out to where the jacket touches the lands improves accuracy so I placed a bullet in a case & locked it in the chamber to see where it stopped.

In my rifle the bullet (Speer 100 grain) touches the lands well before reaching the cannelure. I usually seat so that I crimp at the cannelure (I thought that was what it was for). Is crimping before reaching the cannelure going to be a problem?

No, but seating into the lands might increase pressure so you will want to start with staring loads, good idea anyway.

If your concern is making the best ammunition is the goal, you might be interested in buying of building tools to measure runout of finished rounds.

From my experience, I have seen some rounds that had runout after loaded and once pushed into the lands and subsequently ejected and measured are perfect.

So that, press, case, die, bullet, barrel, combination didn’t have as much factor on the end result as the OAL.

Unfortunately, to know what yours will do will encompass you finding out all of the other things that don’t work better.

They are not all the same and every time I think I have it figured out, I learn something new.

My best advice would be to set an accuracy goal. At least you have a stopping point.

“Maximum” is never ending.
 
My goal is to shoot sub MOA 3-shot groups. I believe my rifle can do that with the right ammunition. Right now I seem to always have one spoiler that widens things up & I don't think it's me.
 
A few thoughts... (I’ve been shooting the .243 for 48yrs)
1. Some of the older Rugers have pretty crummy barrels. You may, or may not be able to improve on the accuracy.
2. DON’T use a bullet with a cannelure for best accuracy. I expect bullets with cannelures to exceed 1moa, at best... even “match” bullets...
3. My best .243 load in several rifles is either a Sierra, Speer, or Nosler 100gr bullet over 41.5gr of IMR4350. I typically just seat to 2.675” oal. This is .025” over the SAAMI max length of 2.650” for the .243. But, it fits and works in every .243 I’ve run them through. My current .243, a Marlin X7S, shoots 5 under 0.75”.
And this.....
 

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Ive read that some Rugers were not good shooters but I don't believe mine is one of them.
I don't believe barrel temperature or cleanliness is the problem because it would then only happen during my first group. I often shoot several groups & the "off" round seems to be fairly consistent, 2 close shots with one a bit off to spoil the group. Often the entire group is within or very close to MOA. But if I could keep eliminate the flyer my groups would be 0.75 inches or even better.
I don't believe I'm causing the problem but I can't rule it completely out either. I limit my groups to 3- shots because my barrel is slim & I don't want heat to be an issue but maybe it would help if I increase my shot groups from 3 to 5?
 
Ive read that some Rugers were not good shooters but I don't believe mine is one of them.
I don't believe barrel temperature or cleanliness is the problem because it would then only happen during my first group. I often shoot several groups & the "off" round seems to be fairly consistent, 2 close shots with one a bit off to spoil the group. Often the entire group is within or very close to MOA. But if I could keep eliminate the flyer my groups would be 0.75 inches or even better.
I don't believe I'm causing the problem but I can't rule it completely out either. I limit my groups to 3- shots because my barrel is slim & I don't want heat to be an issue but maybe it would help if I increase my shot groups from 3 to 5?
5 shots and let the gun cool between shots. Also make sure you have a solid rest.
 
Ive read that some Rugers were not good shooters but I don't believe mine is one of them.
I don't believe barrel temperature or cleanliness is the problem because it would then only happen during my first group. I often shoot several groups & the "off" round seems to be fairly consistent, 2 close shots with one a bit off to spoil the group. Often the entire group is within or very close to MOA. But if I could keep eliminate the flyer my groups would be 0.75 inches or even better.
I don't believe I'm causing the problem but I can't rule it completely out either. I limit my groups to 3- shots because my barrel is slim & I don't want heat to be an issue but maybe it would help if I increase my shot groups from 3 to 5?
You haven’t really described your rifle or your discipline,that I’ve noticed ‘ without knowing your loading or testing routines etc. I would quickly say your way out of tune.
This could be a number of things like powder choice/ accuracy node or a Bullet selection your rifle / twist rate doesn’t like, as I mentioned earlier seating depth with change the shape of a group and sometimes they’ll look like a shotgun but normally incorrect powder charges will cause the harmonic unbalances were shots can go any direction (ie fliers)
Your own table manners will create fliers as well.
Point in case , it’s widely known/accepted in the Benchrest that the last round of a string that fly’s- its you Bro’
Can you post a picture of your targets
 
My load is 33.5 grains of IMR 3031 behind a 100 grain bullet - estimate muzzle vel. of 2800 fps. Unfortunately no pictures available yet. My rifle is a Ruger 77 purchased new in the early 80's. I shoot at 100 yards sitting down, from a very steady concrete bench using a normal rifle rest. Weather conditions are usually hot & humid & wind is normally not a significant factor.
Like I said I don't rule myself out as a possible cause although I consider myself a better then average shooter. However assuming I was responsible & I eliminated the flyer, my rifle would be shooting 1/2 to sub 3/4 MOA groups at 100 yards. Would that be an unrealistic expectation from a factory hunting rifle?
In case this makes a difference to anyone, my interest is not to win a benchrest competition or anything of that nature. All I want to do is learn a little more about precision reloading & determine how well this particular rifle can perform under optimum conditions.
 
Perfect “
Now that you have defined your mission we can proceed.
Sub Moa rifles are just fine for hunting however to squeeze out additional accuracy there are a few ways to go about it.
Staying with magazine length ammunition will likely limit this goal but if your willing to single load you’ll have additional opportunities.
I start with a known powder for the caliber I’m interested in and Bullet combination to match my mission,
From there finding the lands is essential for my load development process, a Hornday L&L tool with a modified case is very easy to use. Your establishing a cartridge base to ogive Datum (CBTO)
Seating Bullets a couple thousand short of this number is a fairly safe approach with regards to pressure.
I load what’s called a powder charge ladder test starting 10% under max charge load one case each in .2 increments through the max charge listed and using the same point of aim you’ll shoot and record on a second identical target at your bench where each shot hit, continue until signs of pressure such as heavy bolt lift. Stop there.
What you lookin for is a flat spot or node where rounds have the least vertical. I personally load in between those charges.
Once my node is established I will proceed to a seating test.
Below is and example of my personal abbreviated test followed by a seating test.
I chose 29.6 as a starting node then chose .020 jump as a seating depth.
There is more, much more but this is a good start down the rabbit hole
J
 

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A) Don’t crimp.

B) Different bullets will ask for different jump lengths. Secant ogive bullets tend to need minimal jump, or jam. Tangent ogive bullets are more forgiving. Copper solids and partitioned bullets need a lot of jump (50thou plus), while many Hybrid ogive bullets will be happy with anything from 10thou jam to 50thou jump. In general, it’s easy for folks to pass this info around as very accurate starting points for the new user.

C) Touching the lands is bad. Either be jammed in, or off, but don’t seat bullets to “kiss.” It’s a recipe for inconsistency.

D) Jamming in a hunting rifle can be bad. You’ll risk pulling the bullet and dumping powder into your action when you simply try to unload. Jamming is a benchrest game game.

E) Can’t argue with mag length restrictions unless you want to single feed. Only argument you can have in that case is with custom barrels and custom chambers, which match the leade to the mag length. Not so common.
 
In my opinion, if you're chasing accuracy skip the crimp. The 243 has enough neck to have adequate neck tension without needing a crimp.
 
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