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I have spent this morning measuring OAL on my 223 ready to reload and was hoping somebody can help?

 

I have measured the OAL 20 times with my chosen bullet and averaged the result. It has come out as 1.8499". How much of a jump to the lands should I start with please?

 

The OAL gauge instructions say to use 0.02-0.04" off the lands when seating the bullet.

 

So do I start seating my bullets with an OAL of 1.8299"?

 

Sorry for a novice question, want to get it right before I move on to priming and charging etc!

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I have spent this morning measuring OAL on my 223 ready to reload and was hoping somebody can help?

I have measured the OAL 20 times with my chosen bullet and averaged the result. It has come out as 1.8499". How much of a jump to the lands should I start with please?

The OAL gauge instructions say to use 0.02-0.04" off the lands when seating the bullet.

So do I start seating my bullets with an OAL of 1.8299"?

Sorry for a novice question, want to get it right before I move on to priming and charging etc!

I set mine to 20 thou of lands, but make sure they will fit in your magazine

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Dont forget whst you read tecnique like this is relivent to high tolerance target bullets not off the peg humtimg rounds

Many good quality hunying rounds will vary 20 tho in the same box and you can so easy end up with a jamb into the launds. This can mean sinficant presure increases and the possibility of a broken gun and or injury

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Thanks guys. I've just had a play and seated the bullets at 1.8299" and they fit in the magazine no problems and the bolt closes with no resistance whatsoever. I will be loading 50gr vmax for fox - i usually use 40gr Norma factory so this is my first venture into loading my own!

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I use to worry about OAL and jumps but then I started to really mess around with things and banged the bullet in to what the Lee book says the minimum OAL. First did it with the .222 which use to shoot 10mm groups with A-Max and ¼mm off lands.

After pressing the bullet to minimum OAL and testing them group again guess what happened. Nothing, no change what so ever.

I then switched to 40gn varminters, I could not seat .2 of the lands as they are small and not enough is in the case neck. I just pushed them in so 5 mm was in the case. Shoots the same groups as the A-Max did.

 

I now start with all my loadings at minimum OAL and then once I have found the best powder amount I either leave it at that if tight enough or start poking the bullet out a little at a time till its grouped to my needs.

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I use to worry about OAL and jumps but then I started to really mess around with things and banged the bullet in to what the Lee book says the minimum OAL. First did it with the .222 which use to shoot 10mm groups with A-Max and ¼mm off lands.

After pressing the bullet to minimum OAL and testing them group again guess what happened. Nothing, no change what so ever.

I then switched to 40gn varminters, I could not seat .2 of the lands as they are small and not enough is in the case neck. I just pushed them in so 5 mm was in the case. Shoots the same groups as the A-Max did.

 

I now start with all my loadings at minimum OAL and then once I have found the best powder amount I either leave it at that if tight enough or start poking the bullet out a little at a time till its grouped to my needs.

Take a lightweight 55 or 58 grain in a .243 and the bullet ogive wont het any place near the launds. Funny enough most favtory rifles shoot them realy well with jump lengths you can measure with a flipping tape measure!

Your lucky with an off yhe peg rifle if your chamber is perfectly consentric with humtimg bullets mass produced I suggest a few might want to search yhrough a few boxes with a guage

Your findings are far from unusual

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as you are starting out I would only say one thing:

 

IGNORE THIS HYPE ABOUT TOUCHING OR BEING 10 THOU OFF THE LANDS!!

 

Not one single factory round is loaded like this and many will produce ammo better than most people can shoot

 

Start your loads with at least a calibre depth seated into the neck .i.e. for a .224 make sure your bullets are seated at least .224!

as above with short light bullets you will be WAAAAAAY off the lands (unless you have a custom chamber), trying to get them near then lands will leave you with less and less seated and potentially produce bullets with higher run out of concentricity and subsequently LESS ACCURATE

 

Priming and charging learning curve comes before OAL tweaking

get your case prep, charging and load development right and you will see clear indications of where your rifle likes the charge levels to me.

do this with a factory SAMMI spec or OAL indicated by the load manual you are using (or online guides by powder/bullets manufacturers)

 

good luck,

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The main reason, when I use to reload, for sticking a bullet out quite far, for me was so I could get more powder in!

 

i run several compressed loads, not hot ones, just compressed

.222 and 300 Win Mag notably

 

no pressure signs at all,

case on the ,222 is brim full, have to tap it down to even get the bullet to sit in/on the neck without spilling powder!

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IGNORE THIS HYPE ABOUT TOUCHING OR BEING 10 THOU OFF THE LANDS!!

 

Not one single factory round is loaded like this and many will produce ammo better than most people can shoot

 

+1 too much detail, so many other things to get right first

I went really mad a few years ago reaming case necks, reaming flash holes, measuring run out and everything else you could think of. TBH it didn't really make diddly squat difference to my groups as far as I could see.

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If you are measuring and going to the effort load 3 sets of 5 bullets. 5 10 and 15 thou from the lands and shoot them and compare groups. some rifles you will see a marked difference. My rifle I load whatever bullet to 15thou from them and it just works, this gave the tightest groups when I first got it and frankly it just kills stuff so I've never re measured or tried anything else

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What powder are you using with the vmax. What rifle is it also. I can't get anywhere near the lands with my cz due to mag length. I'm using 52g amax loaded to max mag length. About to start using 60g vmax and 52g Sierra matchkings.

2.280" and still not kissing the lands. It's a similar story with the 308. As said stick to sammi specs get it shooting and play with jump to the land and fine tuning later. I'm still fine tuning after 4 years and loads of lead down the range and still half inch groups at 100m.

Edited by Albert 888
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I was using 24.5g of blc2 with cci br primers and 52g amax in ppu brass and hornady my necks are starting to spilt on the 5th firings of the hornady, I'm now switching to norma brass h335 and 52g Sierra matchkings. I ran out of Amax and blc2. My rifle was taking a lot of cleaning, as in 20-30 patches after around 50 shots,don't know if it's the powder primers or bullets, but the switch of powder and bullets may sort it.

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Marnold, I reload for 4 rifles in 223. There are two bits of good advice on this thread - do your experiments using the OCW test and secondly Brewshers statement that that you don't always have to seat bullets right up to the lands. My 20 Tac is seated 222 thou back and will shoot sub.2 my other 2 rifles are seated >100 thou back.

 

With you 223 I would suggest starting 40 thou back just to get things moving - you can always try further out later.

 

You must bear in mind that weight of powder and distance off the lands are not the only ingredient to make an accurate rifle. Case prep is so very important and trying to make your cases clones of each other is equally important.

 

Just to illustrate the links below started off with an OCW test (it is essential that you do this as laid out by the author) on a guys 223 shooting 50 gr Vmax

 

http://s438.photobucket.com/user/wyndog/media/Bradley223_zpsb6b15213.jpg.html

 

And having decided which weight, I played about with seating depth and in this development primers also

 

http://s438.photobucket.com/user/wyndog/media/Bradley%20.223%20A_zpsmg5fp9kc.jpg.html

 

http://s438.photobucket.com/user/wyndog/media/Bradley%20.223%20B_zps0kasf6k1.jpg.html

 

I must confess I weigh bullets and empty case and batch them - I know - a sad person !!

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