Small Primer Pocket .243 Win. Brass

[South Pender]

At the risk of repeating something I mentioned in a thread I started in the Main Message Board, I've been looking for ways to improve the accuracy I'm getting with a Wichita .243 Win. My main thought had been to rebarrel, and I got some good ideas about this in that thread.

However, one option would be get some Lapua .308 Win. Palma Brass, with the small rifle primer pockets and neck it down to .243. This is readily available here. I have been using Lapua .243 Win. brass up to this point. So my question is what kind of improvement might I expect with the small rifle primers over what I've been getting with the regular .243 Win. brass with the large rifle primers. One thing that I wondered about was whether these smaller primers would have enough oomph to ignite the 45-50-gr. charges of powder that I've been using. The fact that this brass is sold to .308 match shooters, however, would seem to suggest that this might not be an issue.

Any thoughts on this?

Edit. I did come across this thread on Shooters' Forum from 2010 that gets into this with .308 Win.

http://forum.accurateshooter.com/threads/308-lapua-small-primer-pocket-brass.3748327/

 

[LA50SHOOTER]

I saw an earlier thread a couple months back on this topic & a few of the guys didn't feel that the "gains" were worth the trouble. - Probably have to neck turn the brass once it was necked down. - Basically their consensus was it was a bunch of work & the gains didn't really justify it. - That doesn't mean you can't give it a try. - The Lapua 243 Win. brass with Lg primer pockets seem pretty good to me.

 

[JLT]

I saw an earlier thread a couple months back on this topic & a few of the guys didn't feel that the "gains" were worth the trouble. - Probably have to neck turn the brass once it was necked down. - Basically their consensus was it was a bunch of work & the gains didn't really justify it. - That doesn't mean you can't give it a try. - The Lapua 243 Win. brass with Lg primer pockets seem pretty good to me.

I agree with LA50SHOOTER. The Lapua .243 brass is really good stuff and has proven to be quite durable with pretty stout loads. I have not tried necking the Palma brass down for .243 - the marginal contribution seems quite small given the amount of work required.

 

[243winxb]

308 to 243. No thank you.

 

[mikeinct]

How many rounds have you fired in that barrel ? Also how many times have you reloaded that Lapua brass..Mike in Ct

 

[watercam]

For me, the small primer brass does make it easier to work up a load and does give incrementally better ES/SD numbers but you may not see a major difference in vertical spread until 600+ yards. The brass does last much longer though (assuming you anneal at least every 3-4 loadings. The Lapua .243 brass tends to crack necks sooner than other brands).

 

[Ringostar]

I'm not sure of a gain, but another option to try here. Peterson is offering 260 small primer brass. It would only be a 1/2 mm neck down.

 

[LA50SHOOTER]

I'm not sure of a gain, but another option to try here. Peterson is offering 260 small primer brass. It would only be a 1/2 mm neck down.

And would be easier going from .26 cal. to .243 than .308 - Good point Ringo !!

 

[riflewoman]

I used to shoot 600 yards with Remington BR brass(308 with small primers) when I shot highpower. My load was 42.2 4064 and a 190 bullet. I found that slower powders were primer sensitive and Rem 7-1/2 were the best. Currently, the Palma shooters load with Varget or RL15... So with that in mind...

Being that the 243 tends to use slower powders, small primers might not give you good ignition. Or at least might not give any better results. Worth a try tho.

 

[Ringostar]

I used to shoot 600 yards with Remington BR brass(308 with small primers) when I shot highpower. My load was 42.2 4064 and a 190 bullet. I found that slower powders were primer sensitive and Rem 7-1/2 were the best. Currently, the Palma shooters load with Varget or RL15... So with that in mind...

Being that the 243 tends to use slower powders, small primers might not give you good ignition. Or at least might not give any better results. Worth a try tho.

They will probably require a small magnum primer.

 

[South Pender]

How many rounds have you fired in that barrel ? Also how many times have you reloaded that Lapua brass..Mike in Ct

I have about 350 rounds down the barrel at this point. Actually, I started out with Federal brass, but switched to Lapua brass for the last 200 rounds or so when I realized it was available. The Lapua brass has had four reloadings at this point.

 

[South Pender]

I'm not sure of a gain, but another option to try here. Peterson is offering 260 small primer brass. It would only be a 1/2 mm neck down.

That's a thought. Is Peterson brass manufactured by them or by someone else? Is it of similar quality to Lapua?

I gather that to resize the necks of .308 brass down to .243, this would have to be done in several steps. Is that true? If so, what would the intermediate steps be?

 

[mikeinct]

I have about 350 rounds down the barrel at this point. Actually, I started out with Federal brass, but switched to Lapua brass for the last 200 rounds or so when I realized it was available. The Lapua brass has had four reloadings at this point.

OK to that bud..You don't weight sort the lot of 100..I cull the top & bottom #20..use those for load development..I reserve the center 60 weight for match use..4 loading's is nothing..Your brass is not tired..good luck...mike

 

[ebb]

I don't think that the small primer brass was intended to give better groups, it was designed to with stand more pressure and have tight primer pockets.

 

[Ringostar]

Some believe that the small primer brass gives lower SD's. I've never tested it though.

 

[South Pender]

I don't think that the small primer brass was intended to give better groups, it was designed to with stand more pressure and have tight primer pockets.

Is that right? I had thought that small primers and the smaller flashhole were seen as likely to produce better accuracy, but I'm willing to learn otherwise.

I'm assuming that the small rifle primer brass also has the smaller (.060") flashhole. I did find this:

http://bulletin.accurateshooter.com...apua-to-introduce-a-small-primer-308-variant/

 

[ebb]

It was made for Palma shooters that were having to load their 308s over pressure to get a load hot enough to get to the 1000yd target. The small pocket means more brass in the case head for pressure to move.

 

[Laurie]

No! No! No!

308 Palma was originally introduced as an experiment at the US Palma Teams' request in order to reduce ES / SD MV values as Palma is only shot over 800-1,000 yards and at 308 Win MVs, ES reduction improves elevations on target, a huge plus.

This was all written up in great detail on the US Rifle Teams' Long Range Shooting Forum by Dan Simpson who oversaw the tests. It followed on from extensive work by US Palma Team shooter Tom Whitaker using the old Remington small primer / flash-hole UBBR brass in Palma competition.

At no time did anybody in Lapua or the Palma teams even mention brass strength and/or running at higher pressures / MVs over the previously employed standard LRP Lapua case, and AFAIK the Palma guys and girls still have the same ballistics as before - the newer 155gn SMK at ~3,050 fps. It was F/TR shooters in the main who discovered this additional benefit and exploited it. (The benefit is twofold - higher MVs OR longer case life especially if annealing is used. Prior to the Lapua Palma, F/TR shooters routinely junked standard brass after 3 to 5 firings because of expanded case-heads / pockets depending on case make and loading.)

The ES/SD reductions are real, and are worth having.

Have a look at my three part feature on this subject which while being primarily about SR primer performance starts by comparing the same load series in standard and Palma Lapua cases in Part 1.

http://www.targetshooter.co.uk

 

[MagnumManiac]

Albeit true that the brass is tougher with SR pockets, the fact that the brass deforms less is what keeps the loads consistent from one loading to the next.
Primer ignition is more uniform resulting in smaller ES/SD numbers. The same is true if you use brass with .058” flash hole size, it just produces more uniform ignition.
I have been using the SR Lapua 22-250 brass to form 22-250AI and the ES/SD shrank to the low teens/single digits without even testing any loads. To say I was amazed is an understatement.

I wish more cases were developed with SR pockets.

Cheers.

 

[Laurie]

I have been using the SR Lapua 22-250 brass to form 22-250AI and the ES/SD shrank to the low teens/single digits without even testing any loads. To say I was amazed is an understatement.

Lapua 22-250 in small primer / flash-hole form? I hadn't heard of that, but it's a logical move.