.243 105 gr AMAX Reloading Help??

[WampusCat]

Why would Lance suggest to neck size down to 2.035 when the powder is high already as is at 2.045. I mean it just doesn't seem logical to me that I would shorten my overall length of casing. If I shortened it to that length it would yield less space hence making more pressure wouldn't it?? Idk just seems a bit far fetched considering the situation with brass space.

He did not suggest neck sizing down! He recommended trimming to length and it is not far fetched at all. The nature of the shape of the 243 shoulder will allow the brass to stretch or "flow" when fired. In fact it will do this more so than other cartridges with sharper shoulder angles. Lance was trying to save you more worker later by taking care of it now. You will still need to trim later.

If you are trying to increase case capacity by allowing a longer neck you are fighting a losing battle.

Are you set on Retumbo? While Retumbo may work, there are many other powders that are better suited to the case capacity of your 243. Lance eluded to this earlier as well. This is especially true if you are worried about crunching the kernels in your compressed load. H-4350, H4831, and RL-17 or even H-1000 might be suited better to your goals. How long is your barrel?

 

Hello guys, so I purchased all the equipment needed to start reloading my own ammo.

 

All specs are good my OAL = 2.760 I have seeded each bullet to 2.765 which is a .15 JUMP from the lans of my rifle.

 

I am a bit confused by this. If you seated your bullets to 2.765 how is your OAL 2.760? How did you measure the distance to the lands of your chamber to know you have a .15 jump?

[lancetkenyon]

A few more clarifications and observations, along with more suggestions.

As Wampuscat helped clear up, OAL of the case @ 2.045" is MAX case length, from base of case to top of neck. All books I have ever read have a "trim to" length of .010-.015" shorter than overall max case length. Meaning you do not have to trim after each firing, you might be able to go 2 or possibly even 3 firings before you need to trim again. If you go OVER this length of 2.045", you run the risk of jamming your case neck past the chamber cut depth, basically creating a strong crimp in the brass to the bullet, greatly increasing pressure upon firing. You will also find it difficult to close the bolt. Cases will stretch and grow by quite a bit. As much as .007" depending on a lot of factors. I can usually only get 2 firings from my .260 Rem (same case as the .243 Win, just necked to .264 vs. .243) before I have to trim when I go with a .010" shorter than max trim length. Both the Hodgdon and Hornady data suggests a "trim to" length of 2.035".

If you are filling the case with enough Retumbo to fill the entire case up to the top of the neck, and that extra .010" lets it all fit, something is wrong.

What case does your book say they are using in their load data? Possibly Winchester (as the Hodgdon data states)? If you do not follow every bit of their recipe, you will have different results. I know that Federal cases have more brass content in every other case I have weighed vs. Winchester, as I hinted at in my earlier post. Some quite a bit more, as much as 25 grains, which reduces the case capacity. In my own early testing, I used data from a book that used Winchester, and I was using Federal brass, and I had pressures quite a bit below the book suggested max.

What are you using to weigh your powder charge? My electronic powder throw and scale are not really that accurate, so I weigh each powder charge again on a beam scale to within a single kernel of powder. My electronic scale is only "accurate" to within .1 grain. Add that to the error factor, and I can see throws vary as much as .3 grains. A 45.8gr throw can actually weigh more than a 46.1gr throw when I double check them with an accurate scale. This does no good for accuracy and consistency.

I would suggest you weigh a new Federal case, and I can weigh one of my .243 head stamped Winchester brand, and I would lay money that it weighs more than the case I have.

Again, I would try a variety of other powders before using Retumbo in a .243 Win if it were me. Even if you were pushing a 115 SMK, 115 DTAC, 115 Berger VLD, 117 Matrix VLD, 120 Matrix RBT, from a 28"+ barrel.

Will Retumbo WORK? Probably. Are there better alternatives out there? Definitely, a lot of them. Are you just trying for the absolute most speed out of the combo?

For starting point, look at as much info as you can. Try here. http://www.reloadersnest.com/frontpage.asp?CaliberID=5 Not a single submission uses Retumbo. The slowest powder I see used is RL25, and one that uses H1000, and IMR7828. There is one guy who submitted a load using VV N170 pushing a 115 VLD w. a 26" 1:8" twist.

Also, note the slower powders pushing heavier bullets mostly have some freebore to get the bullet out a bit before touching the lands. This reduces pressure. Having only .015" jump is not much. But .150" is a lot.

How about a little info on your rifle setup too?

[Kingzero]

Brass trimming is a necessity. If you never trim your brass you could end up jamming the neck into the throat and essentially "crimp" the bullet in the case. This can cause hard chambering and high pressure. Trimming the necks won't affect powder capacity because you never fill up into the neck.

 

Also, are you jumping 0.15" or 0.015"? Because 0.15" is quite a jump to start with if your not restricted by the length of a mag. If you have an accurate way of measuring the chamber, I would start touching the lands or 0.010" off. If you are seating 0.15" try loading them longer (if possible) and you might not get the powder crunch.

 

And not to beat a dead horse...Retumbo wouldn't be my first choice for a 243. The velocity in that data is ok but with other powders you can get better. I shoot 105 Amax's in a 6mm Creedmoor (very similar) and get 2950 fps with a 20" barrel using H4350. If I had a 24" barrel like used for that Hoddgdon load data I could probably get close to 3100 fps.

[Couzer]

If retumbo is all you have and your getting results you are satisfied with then why not? Are there better powders out there, yes. When I first started reloading I only used a few powders to load many different types of cartidges. Kept it simple and I recommend keeping it simple as you are just scratching the surface of a whole another world.

Let us know how it shoots!

[roninflag]

I currently load for 6 different .243s. what rifle are you loading for?? scope?

[lancetkenyon]

If retumbo is all you have and your getting results you are satisfied with then why not? Are there better powders out there, yes. When I first started reloading I only used a few powders to load many different types of cartidges. Kept it simple and I recommend keeping it simple as you are just scratching the surface of a whole another world.

Let us know how it shoots!

I agree with this.

 

I only use a four powders for 95% of my reloading. Varget (.223 69SMK, .22-250 52SMK), Benchmark (.223 50V-Max, .260 95V-Max, 6.5 SLR 95V-Max), H4350 (.260 127LRX, .260 140HVLD, 6.5 SLR 127LRX, 6.5 SLR 140HVLD), H1000 (.25-06AI 115HVLD, 6.5-06AI 140SMK, 7RM 168HVLD/180Hybrid, .300RUM 210HVLD/215Hybrid, .300WM 210HVLD).

 

I have a few other powders on hand for load development or reloading of other people's cartridges. H4831SC (for my .25-06AI fire forming loads if I ever need to run a new batch, and a few other .270 Win/.280 Rem I load for other people) and RL22 (for three other 7RMs I load for).

[WampusCat]

If retumbo is all you have and your getting results you are satisfied with then why not? Are there better powders out there, yes.

 

Kept it simple and I recommend keeping it simple as you are just scratching the surface of a whole another world.

 

I assumed he wasn't satisfied with his results. I agree he should keep it simple as he is clearly just beginning. For $25 he could have one of the mentioned powders that eliminates one of his obstacles already, and likely be used in another common chamber he may own.

[Coues Archer]

A few more clarifications and observations, along with more suggestions.

 

As Wampuscat helped clear up, OAL of the case @ 2.045" is MAX case length, from base of case to top of neck. All books I have ever read have a "trim to" length of .010-.015" shorter than overall max case length. Meaning you do not have to trim after each firing, you might be able to go 2 or possibly even 3 firings before you need to trim again. If you go OVER this length of 2.045", you run the risk of jamming your case neck past the chamber cut depth, basically creating a strong crimp in the brass to the bullet, greatly increasing pressure upon firing. You will also find it difficult to close the bolt. Cases will stretch and grow by quite a bit. As much as .007" depending on a lot of factors. I can usually only get 2 firings from my .260 Rem (same case as the .243 Win, just necked to .264 vs. .243) before I have to trim when I go with a .010" shorter than max trim length. Both the Hodgdon and Hornady data suggests a "trim to" length of 2.035".

 

If you are filling the case with enough Retumbo to fill the entire case up to the top of the neck, and that extra .010" lets it all fit, something is wrong.

 

What case does your book say they are using in their load data? Possibly Winchester (as the Hodgdon data states)? If you do not follow every bit of their recipe, you will have different results. I know that Federal cases have more brass content in every other case I have weighed vs. Winchester, as I hinted at in my earlier post. Some quite a bit more, as much as 25 grains, which reduces the case capacity. In my own early testing, I used data from a book that used Winchester, and I was using Federal brass, and I had pressures quite a bit below the book suggested max.

 

What are you using to weigh your powder charge? My electronic powder throw and scale are not really that accurate, so I weigh each powder charge again on a beam scale to within a single kernel of powder. My electronic scale is only "accurate" to within .1 grain. Add that to the error factor, and I can see throws vary as much as .3 grains. A 45.8gr throw can actually weigh more than a 46.1gr throw when I double check them with an accurate scale. This does no good for accuracy and consistency.

 

I would suggest you weigh a new Federal case, and I can weigh one of my .243 head stamped Winchester brand, and I would lay money that it weighs more than the case I have.

 

Again, I would try a variety of other powders before using Retumbo in a .243 Win if it were me. Even if you were pushing a 115 SMK, 115 DTAC, 115 Berger VLD, 117 Matrix VLD, 120 Matrix RBT, from a 28"+ barrel.

 

Will Retumbo WORK? Probably. Are there better alternatives out there? Definitely, a lot of them. Are you just trying for the absolute most speed out of the combo?

 

For starting point, look at as much info as you can. Try here. http://www.reloadersnest.com/frontpage.asp?CaliberID=5 Not a single submission uses Retumbo. The slowest powder I see used is RL25, and one that uses H1000, and IMR7828. There is one guy who submitted a load using VV N170 pushing a 115 VLD w. a 26" 1:8" twist.

 

Also, note the slower powders pushing heavier bullets mostly have some freebore to get the bullet out a bit before touching the lands. This reduces pressure. Having only .015" jump is not much. But .150" is a lot.

 

How about a little info on your rifle setup too?

 

Hello Lance thank you for your advice; I greatly appreciate it. I have yet to shoot any loads I was just wanting some advice before I left to the shooting range. The brass discussed in this book was using Winchester brass, so yes I most definitely will experience some deviations with federal brass. Also I meant to say ".015 jump" not .15 lol yeah that is a huge jump in seating. Another thing that I totally agree with you is the scale, I am currently using a Hornady electronic scale but like you said there is definitely some percent error within its measurement, I will be ordering a beam scale like you suggested.

[Coues Archer]

 

Why would Lance suggest to neck size down to 2.035 when the powder is high already as is at 2.045. I mean it just doesn't seem logical to me that I would shorten my overall length of casing. If I shortened it to that length it would yield less space hence making more pressure wouldn't it?? Idk just seems a bit far fetched considering the situation with brass space.

He did not suggest neck sizing down! He recommended trimming to length and it is not far fetched at all. The nature of the shape of the 243 shoulder will allow the brass to stretch or "flow" when fired. In fact it will do this more so than other cartridges with sharper shoulder angles. Lance was trying to save you more worker later by taking care of it now. You will still need to trim later.

If you are trying to increase case capacity by allowing a longer neck you are fighting a losing battle.

Are you set on Retumbo? While Retumbo may work, there are many other powders that are better suited to the case capacity of your 243. Lance eluded to this earlier as well. This is especially true if you are worried about crunching the kernels in your compressed load. H-4350, H4831, and RL-17 or even H-1000 might be suited better to your goals. How long is your barrel?

 

Hello guys, so I purchased all the equipment needed to start reloading my own ammo.

 

All specs are good my OAL = 2.760 I have seeded each bullet to 2.765 which is a .15 JUMP from the lans of my rifle.

 

I am a bit confused by this. If you seated your bullets to 2.765 how is your OAL 2.760? How did you measure the distance to the lands of your chamber to know you have a .15 jump?

 

The OAL of 2.760 was the suggested min OAL discussed in the book. And the way I got the lans measurement is I used one of the federal brass casings I have and neck sized it till I could successfully pass through an amax with slight tension. From there I colored the walls of the bullet with sharpie and stuck it into my rifle, completely closed the bolt; pulled out the bullet and checked the seating depth as well as COAL and that's how I got my measurement. It was suggested to do this 3 times to get a good guesstimate the mean value of those measurement came out to roughly 2.780

[Coues Archer]

And yes I will probably have to get a different powder but this powder was on clearance at my local retailer. I got it for really cheap; so yeah that explains why I got it haha.

[roninflag]

what rifle? how did you select your projectile?

[azsugarbear]

I shoot the Berger 105 gr. in my 243 rather than the A-max, but load development should be close. My Model Seven wears a custom Brux barrel with a 1:9 twist. I started out with the typical powders: 4350, 4831sc, etc., but I was never completely satisfied with either the velocity or the accuracy. I ended up with good nodes at 47.2 to 47.5 grains of Retumbo. My final load is 47.4 gr. of Retumbo with an ave. velocity of 3,100 fps. Great Coues medicine.

 

Please note: This is a very "warm" load for my rifle. You should be cautious and work up slowly. I use Lapua brass because it seems to tolerate high pressure better than the other brands. Plus I get many more reloads out of it. Primers are Federal 215 LR magnum primers.

 

I used to set my filled brass on the dryer while it was running. The vibration would settles the powder down into the case. Made me feel a little better. Anymore, I just drop the powder in and compress with the bullet. Same results either way. Happy hunting.

[Zeke-BE]

I shoot the Berger 105 gr. in my 243 rather than the A-max, but load development should be close. My Model Seven wears a custom Brux barrel with a 1:9 twist. I started out with the typical powders: 4350, 4831sc, etc., but I was never completely satisfied with either the velocity or the accuracy. I ended up with good nodes at 47.2 to 47.5 grains of Retumbo. My final load is 47.4 gr. of Retumbo with an ave. velocity of 3,100 fps. Great Coues medicine.

 

Please note: This is a very "warm" load for my rifle. You should be cautious and work up slowly. I use Lapua brass because it seems to tolerate high pressure better than the other brands. Plus I get many more reloads out of it. Primers are Federal 245 LR magnum primers.

 

I used to set my filled brass on the dryer while it was running. The vibration would settles the powder down into the case. Made me feel a little better. Anymore, I just drop the powder in and compress with the bullet. Same results either way. Happy hunting.

 

 

Great idea with the dryer trick