.243 Win 75gr out of a 20"

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Nathan22Outdoors

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Looking for some guidance, never reloaded before but I have a buddy thats willing to give a hand with the equipment.

I'm looking to shoot the 75gr VMAX or Possibly the 80gr ELDVT out of a 20" barrel. Trying to do research but having a bit of trouble as most 20" loads are for a 100gr and most 70gr loads are for 24 and 26" barrels.

Some powders I've tried looking at (but not limited to) are:
H4350, Varget, Staball 6.5, H4395, N160

Any insight, experience and suggestions?
 
I wouldn't worry too much about barrel length, most companies publish load data with a longer barrel to show peak velocity (often times with a completely inappropriate twist rate for the bullet). I had a 243 barrel chopped down to 20", I lost maybe 100 fps but it actually tightened up some (less whip). I have the most experience with Varget, and use it a lot for hunting loads. It won't give peak velocity most of the time, but it is temp stable, and I find it much less "blasty" (for lack of a better term) in short barrels. Boilerplate advice: Start low and work up, watching for pressure signs. I rarely try and push for max speeds for any of my rifles, especially for overbore cartridges like the 243. A 75 or 80 grain bullet, at 3000+ fps will take care of any critter the bullets are designed for. Unless you are just punching paper, and then it doesn't really matter as long as you get the accuracy you are after.
 
jparent said:
I wouldn't worry too much about barrel length, most companies publish load data with a longer barrel to show peak velocity (often times with a completely inappropriate twist rate for the bullet). I had a 243 barrel chopped down to 20", I lost maybe 100 fps but it actually tightened up some (less whip). I have the most experience with Varget, and use it a lot for hunting loads. It won't give peak velocity most of the time, but it is temp stable, and I find it much less "blasty" (for lack of a better term) in short barrels. Boilerplate advice: Start low and work up, watching for pressure signs. I rarely try and push for max speeds for any of my rifles, especially for overbore cartridges like the 243. A 75 or 80 grain bullet, at 3000+ fps will take care of any critter the bullets are designed for. Unless you are just punching paper, and then it doesn't really matter as long as you get the accuracy you are after.
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Thankyou for the reply and tips. Will keep it all in mind.
 
jparent said:
I wouldn't worry too much about barrel length, most companies publish load data with a longer barrel to show peak velocity (often times with a completely inappropriate twist rate for the bullet). I had a 243 barrel chopped down to 20", I lost maybe 100 fps but it actually tightened up some (less whip). I have the most experience with Varget, and use it a lot for hunting loads. It won't give peak velocity most of the time, but it is temp stable, and I find it much less "blasty" (for lack of a better term) in short barrels. Boilerplate advice: Start low and work up, watching for pressure signs. I rarely try and push for max speeds for any of my rifles, especially for overbore cartridges like the 243. A 75 or 80 grain bullet, at 3000+ fps will take care of any critter the bullets are designed for. Unless you are just punching paper, and then it doesn't really matter as long as you get the accuracy you are after.
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THIS ^^^^

20in is a lil short for 243 as it wont burn all of its powder so there will be a velocity reduc tion and blast increase vs a longer bbl.

That said...as explained above the velocity loss isnt amajor factor unless you are pushing for max velocity for extened range and or absolutely need every scrap of energy....in which case you would be/should be using a longer bbl anyway.

Since you are new to reloading you should be cautious with loads anyway....learning and then being observant for overpressure evidence and or issues is a skill to be learned....stick to well proven published data and the advice of your experienced reloader certainly to start.

The 243 has plenty of velocity/power especially for lightweight bullets like the range you are using so doesnt need to be pushed hard....you will get plenty of performance out of your 20in bbl running standard pressures.....use good hearing protection...short 243s are LOUD
 
terez said:
THIS ^^^^

20in is a lil short for 243 as it wont burn all of its powder so there will be a velocity reduc tion and blast increase vs a longer bbl.

That said...as explained above the velocity loss isnt amajor factor unless you are pushing for max velocity for extened range and or absolutely need every scrap of energy....in which case you would be/should be using a longer bbl anyway.

Since you are new to reloading you should be cautious with loads anyway....learning and then being observant for overpressure evidence and or issues is a skill to be learned....stick to well proven published data and the advice of your experienced reloader certainly to start.

The 243 has plenty of velocity/power especially for lightweight bullets like the range you are using so doesnt need to be pushed hard....you will get plenty of performance out of your 20in bbl running standard pressures.....use good hearing protection...short 243s are LOUD
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Thankyou, im using the guidance of my buddy that reloads, infact he might even be the one doing the reloads for me if I supply the components. I will definitely make sure to be careful and slowly work my way up. It is definitely loud, it also has a 3 port brake so she barks. I'm planning to hunt coyotes put to maybe 400 so im not trying to squeeze every ounce of velocity out of it. Just something decently quick, accurate but consistent ofcourse.
 
OP - do not get overly "married" to that bullet weight or brand - your rifle will eventually tell you what works best in it. I happen to own a Ruger 77 Hawkeye in 243 Win - a very short barrel - 16.5". This one happens to like 95 grain SST - at least the Hornady factory ammo with that bullet will put two holes touching at 100 yards - it has done that 3 or 4 times now - good enough for me.

There are six boxes Hornady ammo here - same lot number as the box that shot so well, on the initial go-around. I have not re-loaded for it yet.
 
Nathan22Outdoors said:
Yep, I haven't gave it to him yet since I don't have the components but he said he will need it for setting/measuring the ogive
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very good any reloading done one must have the rifle in hand for setting specifics
a good place to start is with a known accuracy load i use the nosler manual look at the most accurate powder listed for the bulletin weight you want to use that being said it does not have to be the nosler brand billetalso flat based bullets have a tendency to be more accurate than botail billets
unless you plan to shoot past 500-600 yds their is know advantage to a botaill bullet
 
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Dont think im adding anything new here but do shoot a 20" 243 BSA so I thought I'd give my 2cents.
Like others have stated, don't think too much about the barrel length. Just load min charge and work your way up and see how it goes. I find that printed data doesn't often match real word testing. It'll be close usually but I've had surprises.
Barrels are like fingerprints. No two are the same. Imr4064 has been great. Same with varget with bullets 70-85gr.
I tried 85gr sierra bt with ramshot big game recently and was almost 200ft/sec below their listed speed but good accuracy. Other powders have been close to listed speeds.
Extremely impressive accuracy for an inexpensive bullet btw.
Gotta get out and chronograph to see.
Try as many powders as you can. I don't think I've ever noticed a diff in muzzle blast.
I'd give Berger the nod for "most accurate" load data overall for what it's worth.
Good luck to you. Great caliber
 
struff55 said:
very good any reloading done one must have the rifle in hand for setting specifics
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Yeah for sure, hopefully after I get the components I can bring him the rifle, get stuff set up and hopefully ladder test different charges and find something my rifle likes. Even the factory ammo shot very well out of it (I'd hope because it's a custom rifle) but I had some weird instances that im not sure if it was my fault, or the ammo, or something else. For example I had a 5 round magazine loaded with winchesters new 65gr VarmintX. Put all 5 in 1 ragged hole, im thinking mint, thats great, then I tried printing a 10 round group off that first 5. Not sure if the barrel was getting too hot (very possible) or if i accidently loaded the 2nd mag with different ammo (I was testing 2 different types of winchester and 3 different types of federal and hornady that day) so I could've easily put a different ammo in the 2nd mag. But my group went from 5 rounds in 3/8" (first mag) and the second mag was completely all over the place opening it to about 1 5/8. Now I understand this could've very well been a hot barrel or error on my part, I don't think habdloading will instantly fix that and magically make my rifle put 10 rounds in 1 hole. I just want to cut out the variable of inconsistent ammo while also shooting the bullet of my choosing.
 
scotteboy said:
Dont think im adding anything new here but do shoot a 20" 243 BSA so I thought I'd give my 2cents.
Like others have stated, don't think too much about the barrel length. Just load min charge and work your way up and see how it goes. I find that printed data doesn't often match real word testing. It'll be close usually but I've had surprises.
Barrels are like fingerprints. No two are the same. Imr4064 has been great. Same with varget with bullets 70-85gr.
I tried 85gr sierra bt with ramshot big game recently and was almost 200ft/sec below their listed speed but good accuracy. Other powders have been close to listed speeds.
Extremely impressive accuracy for an inexpensive bullet btw.
Gotta get out and chronograph to see.
Try as many powders as you can. I don't think I've ever noticed a diff in muzzle blast.
I'd give Berger the nod for "most accurate" load data overall for what it's worth.
Good luck to you. Great caliber
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Thank you, and I agree, 243 is amazing, I think its the best 308 offspring
 
I shoot an 18.5” slightly modded M700.
I load 85gr Barnes TSX and i get 2800fps out if it with 36.5gr Varget. Zero pressure issues.
I used to use H4895 but switched for some reason I don’t recall.
It’s Very accurate too but it does sit in a rather snazzy MDT chassis.
I also have a Heathen 3 port on it.
 

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Beeron said:
I shoot an 18.5”
I load 85gr Barnes TSX and i get 2800fps out if it with 36.5gr Varget. Zero pressure issues.
I used to use H4895 but switched for some reason I don’t recall.
It’s Very accurate too but it does sit in a rather snazzy MDT chassis.
I also have a Heathen 3 port on it.
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Sounds like a nice build. I'll post pictures of mine in a few minutes
 
Nathan22Outdoors said:
Seemed to be the standard for any 20" 243 factory rifle. Figured it was my best bet
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It was standard for a long time, but other brands went with faster twist rates. Savage uses 1:9.25, Remington used 1:9.125 for a while and just switched to 1:8, Tikka just switched to 1:8, some have used 1:9, it's all a part of the pivot to long and heavy-for-calibre bullets.

The SAAMI drawing specifies a 1:10 twist so factory ammunition conforming to the SAAMI specification needs to stabilize in that twist rate. I would usually just try to find the most accurate factory load use that as the basis for my handloads.

My 20" .243 really likes the 80gr Federal blue box and seems to shoot the 80-90gr stuff better than the 100gr bullets, but each gun is different in that respect.

If there is a good-performing factory load with a commercially available bullet I would aim to duplicate that. With good components behind the same bullet loaded to similar overall length you should get pretty close, then tune from there.
 
Nathan22Outdoors said:
Thank you, and I agree, 243 is amazing, I think its the best 308 offspring
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243 is cool, but 7mm08 is the best 308-based cartridge lol

As everyone else has said, barrel length is not a huge factor. Yeah, you'll lose a bit of velocity, something like 25-30fps per inch vs listed velocities on a 24-26" barrel, but considering you've got a 1:10 twist it's not like this is a build for super long range work so you'll be fine. 3300fps vs 3400fps isn't a big deal at moderate ranges.

My Speer #12 uses a 22" barrel for their data:
ab17782f-cb46-4776-bec9-7d1c63c9cec4-1_all_14348.jpg1000021935.jpg
 
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