.243 Winchester from scratch

  • Last Post 16 April 2017
Scearcy posted this 21 January 2017

There seems to be growing interest among our ranks in shooting smaller calibers.  Much of the attention has been directed to the 223 and 22-250.  This is a good thing as John A, Joe B and others have been providing some real education for me, at least. Rather than following directly in their foot prints I have decided to try to use a 243 Win for this summers matches.  There is precedent as our National Champion about 10 years ago used a 243.  I believe Paul Pollard and his son are also using a 243. 

I have 2-243 Win rifles which will qualify in the Hunter class.  Being neither a machinist nor a skilled artisan I prefer to work with over the counter rifles.  I am telling you this because some of you, more skilled than I, are going to offer advice that I do not have the skills or tools to implement.  What I will share is an unedited pursuit of acceptable accuracy from a rifle I already own.


Order By: Standard | Newest | Votes
Scearcy posted this 21 January 2017

For the record, my rifles are a Remington 700 and a Tikka Hunter.  Both are standard weight rifles and are unaltered in any way.  I can post pictures if anyone is interested.  Both are equipped with scopes of at least 20X.

A couple of months ago I posted a WTB for a 243 mold.  I was able to find three: RCBS 243-95-SP, Lyman 245496 and an Eagan 90 gr.  I have cast 500  of the RCBS and Lyman bullets.  I will post pictures of these yet today.

I intend to use a Lee push through sizing die but have been unable to find one locally.  I will be ordering one today but it will be several days before I am able to begin shooting my own bullets.  In the mean time I am going to compare the two rifles using reduced jackets loads and also using a small supply of RCBS bullets that came with the mold.  My plan is to shoot about 100 rounds out of each rifle.  By that time I am hopeful that one or the other will emerge as more accurate. 

Ken Campbell Iowa posted this 21 January 2017

hi mr. scearcy ... this should be interesting ... i too am mostly interested in the 6mm for cast accuracy  ...   keep us informed as to factory rifle choice, bullets, loads, and results ...

my other gun hobby/sickness besides shooting, is trading guns ... i need to hang onto a 6mm or two long enough to get one under 2 moa with cast  ... heh ... i am currently down to a factory barreled rem 700 rechambered to 243 AI, tight neck .... if joeb is right about larger cases doing just fine, maybe i can set some coke cans out to 150 yards !!   i also am down to one old NEI mold in 6mm , it has never shot that great in the past .... but i never used a bullet squisher then ...

joeb has achieved a great 1.5 moa with cast 224 with a good mold, squisher or no squisher,  but if a bullet shoots 5 moa in a good rifle isn't it because the bullet needs squished to fit better ?? 


Scearcy posted this 21 January 2017

Hi Ken

I enjoyed your input last winter when my project was that CZ 308. I would be happy to send you some of my 243 bullets as I go forward. I will squish them first though I think.  I am also going to use 45-45-10 lube at least initially.


Scearcy posted this 21 January 2017

Here are the Lyman and RCBS bullets. I may add rough dimension drawings as we go forward.

  • Liked by
  • Maven
Ken Campbell Iowa posted this 21 January 2017

jim ... those rcbs bullets look like they should work ... what are the dimensions on the bands and the nose ?? ....


tturner53 posted this 21 January 2017

Keep the updates coming. I'm rooting for ya. I have similar stuff and have messed around with the .243.

Scearcy posted this 21 January 2017


The RCBS bullets are .246 +/- .005 on the bands.  The nose right ahead of the first band is .239.  The nose does begin to taper.  I may need to get an NOE nose size die.


Scearcy posted this 21 January 2017

Here are my first test loads.  The jacketed bullet is the 70 gr Nosler ahead of 20 gr of H4198.  The cast load is the RCBS bullet seated as deep as it can be w/o going below the neck.  The cast load is charged with 17 gr of H4198.  Velocity unknown.

  • Liked by
  • Maven
JeffinNZ posted this 21 January 2017

Holy moly.  Those are too pretty to shoot!

Interestingly Al at NOE has been doing runs of Eagan copies.  He did a 6mm but is not showing any in stock.



Cheers from New Zealand

Maven posted this 22 January 2017

For what it's worth, I use the Lyman #245496 @ .244” in my Ruger #1 and am very pleased with its accuracy.  Generally I'll use 14 - 15 gr. of IMR 4198 (or equivalent), but lately it has been 9 - 10 gr. of Unique.  No reason your rifles (or mine) can't be competitive.

BHyett posted this 22 January 2017

I have prejudices based on years of shooting the 6mm bore for fun and sometimes profit. The 6mm bore intrigued me when I first started varmint shooting and that carried over into cast bullets. I even tried cast in a 6X47 with 1 in 14: twist, but not successfully. Now that I'm retired, I plan on an organized testing with several guns to see what can be done. 

Thoughts: Monotype and linotype are the alloys, .244 and .245 are the sizing dies, high-speed lube, and the heavier bullets resist wind markedly better. You can push the bullets to 2300 feet per second with proper fit to the leade. Most bullets drop from the mold between .244 and .245 needing little sizing to seat the gas check. 


  • RCBS 243-95-SP (Best mold for fit and accuracy)
  • RCBS 24-100-FN (Too long, needs special throating to extend leade)
  • SAECO 243 TCGC 85 grain (Great accuracy, shot well at 2300 feet per second)
  • SAECO 243 TCGC 75 grain (Too light, got blown all over at 200 yards)
  • EAGAN 6mm 68 grain TCGC (Bought for 6X47, need toi reevaluate now that I have more experience) 


  • Savage Striker: 6mm BR
  • Savage 99: .243 Winchester
  • Remington XP-100: 6X45
  • Remington 788: 6X47
  • Ruger #1: 6mm Remington 

Country boy from Illinois in the magical Pacific Northwest

Scearcy posted this 23 January 2017


You are way ahead of me. Thats a good thing.  I have a  rifle just sitting around which could be rebarreled.  I have been thinking of some variation on the 6/22-250.  Case volume looks good for a 90-100 gr bullet.  It is going to need to wait a bit until I sort out these two 243s, though.  Can a person get to 1"- 10 shot groups with a standard 243 - in your opinion?


BHyett posted this 23 January 2017

I have been thinking of some variation on the 6/22-250. -  Three decades ago, I built a 6mm-.250 on a trued 788 action for the CBA Silhouette Class and then the CBA closed the class. Using R-P .250 Savage brass with necks turned to clean up to uniform thickness, the rifle shot cast bullets well. I have an affectation for any cartridge built from the .250 Savage case. However, today I use the 6mm BR since the case volume is similar and the brass does not need formed. I still have the barrel and might reinstall it to experiment.

Case volume looks good for a 90-100 gr bullet. -  It is, you get consistent velocity. I mainly used RCBS 243-95-SP and SAECO 85 grain TCGC bullets, Reloder #7 powder, monotype and Linotype, sized .244, high-speed LBT Blue lube, with good results. The rifle was light and hard to steer from sear release to bullet exit. It is analogous to shooting 200 yards with the .22 LR for ASSRA matches, you can influence the path of the bullet while it is still in the barrel.. That is why I worked velocity up to the 2200/2300 feet per second range to help steer the rifle better.

It is going to need to wait a bit until I sort out these two 243s, though. - I have a .243 Winchester Model 70 Varmint converted to a High-Power Target configuration. My hope was to shoot cast at 200 and 300 yards with jacketed at 600 yards. However, I changed jobs and never again had time to shoot High-Power matches. The rifle showed promise at 200 yards, but the cast did not hold up at an actual 300 yards. Velocity variations caused vertical stringing. I went back to H-4831 and the Sierra 100 grain soft point boattail bullet for all ranges. 

Can a person get to 1"- 10 shot groups with a standard 243 - in your opinion? - I think your goal is possible. My first experience was the Ruger #1 in 6 mm Remington that shot well. Several 10-shot groups under an inch with the RCBS bullet. 

Discussing 6 mm cast bullets with Mike Mohler at Fairfax, we had several observations. Mike felt he had so work the bore smooth and be very consistent with powder charge. I agreed with his observation. We discussed gas checks and their quality, a major stumbling block in 6 mm cast bullets. You can see the height of the shank varying from one side to the other on certain lots of gas checks. Sorting these gas checks, they do not shoot as well. Gas check quality is seldom checked. 


Country boy from Illinois in the magical Pacific Northwest

Scearcy posted this 24 January 2017

I made it to the range today.  It is kind of cold but I did shoot all 50 rounds I had along  30 rounds contained jacketed bullets and the balance were RCBS 95 gr.  The jackets were loaded with 20 gr of 4198 which is a reduced load out of a 50 year old Speer manual.  The cast were loaded with 17 gr of 4198 for no particular good reason. 

Most of the shooting was done with a Remington 700 which had less than 100 rounds through it.  I shot 2 groups with jacketed bullets to try to get a handle on the potential of the rifle.  This load is of course not an accuracy load but it is approximately the right velocity for a cast load.  The 2 groups were 1.25” and 1.35” respectively. Pictures

of these two groups are shown below.

In addition I shot 4 - 5 shot groups with the RCBS cast bullet.  I cleaned with Ed's Red between every group.  The group sizes were: 3.35", 2.45", 2.15” and 2.12".  This is the order in which they were shot.  I guess a load which is basically a 2” load on the very first attempt is not too bad. 

Scearcy posted this 24 January 2017

I also shot one jacketed group with a new Tikka rifle.  These were the first shots fired through this rifle.  Unfortunately I could not try cast in this rifle today as it has a tighter throat than the Remington and would not chamber the loads I had.  The one group I did fire was .71".  Considering that this group contains the 3rd through 11th rounds ever fired in this rifle, I am very pleased.


Scearcy posted this 24 January 2017

I have a handful of lubed bullets still available so I intend to load them tomorrow and take the Tikka back to the range.  The bullets will need to be seated a little below the neck to chamber but so be it since they are available.  I am going to change powder also.  There are several loads shown in the Lyman 48th Edition.  The 243 has been dropped from the 50th Edition I guess.


Scearcy posted this 24 January 2017

BHyett,  Thank you for all of the info.  I wonder if one of the specialty gas check makers might be worth a try.  I have a new box of Hornady checks.  I will look them over tomorrow.


BHyett posted this 24 January 2017

At the time of the Nationals in Fairfax, Hornady had announced they were not making any more 6 mm gas checks. Their 6 mm forming  die had broken and there was not enough sales market to recover the cost of repair.  Mike bought all he could find, I believe he had forty unopened boxes. I had fifteen unopened boxes which will usually wear out a barrel. For the next year, I haunted guns shows and old gun shops where I picked up four more boxes. 

We discussed the possibility that the bad gas checks were coming off the die before the forming die broke. Today, possibly, Hornady has new dies, or rebuilt dies, and these checks are good. I would check them to be sure.  

Country boy from Illinois in the magical Pacific Northwest

John Alexander posted this 24 January 2017

Bud didn't mention that the late Mike Mohler won all the marbles with his Ruger 243 at the 2007 nationals in Fairfax  taking home the grand champion trophy.  Mike still holds three national records set with the same rifle.

I am glad to see that you are going to give the 243 a try Jim.  I'm sure you will give it a good workout and I look forward to read the results. I have been poring over the first three year's of the Fouling Shot gathering info for writing an early history of the CBA.  In one of the first matches the first three places were taken by 6mm rifles.  One of the very first CBA postal matches was won with a 223 (Norm D.) and a 222 (me) placed second.  Shortly after that almost all CBA shooters fell in line with 30 caliber rifles.  It is past time for a little more variety.


Scearcy posted this 24 January 2017

Thanks for the kind words, John. 

It is going to snow here  the next 36 hours.  I still intend to get to the range briefly - a Minnesota rifle has to shoot in the snow. There should be an opportunity to try the Eagan mold also.  I have never owned a genuine Eagan so I am excited to try these bullets.  

The reduced recoil of a 243 was one of my goals in this pursuit.  The older I get, the less I tolerate getting kicked.


Show More Posts