308Win Large Rifle vs. Small Rifle Primers

[ddjchemist]

Is there any accuracy difference between large rifle vs. small rifle primers. I am slowly running out of Federal G210M primers that I use for my 308Win custom rifle. I just purchased 2 bricks of Federal G205M primers, so I was wondering if I should expect any change in accuracy. My rifle has heavy Krieger 20" varmint barrel and with Federal G210M it shoots sub-1/2 MOA groups all the time (half groups are 1/4 MOA groups). Will Federal G205M offer the same accuracy? Of course, I have to start using brass with small rifle primer pockets and re-do load development.

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[Local Loader]

Large rifle primers have a taller, wider and thicker cap than small rifle plus more primer material.

 

[ddjchemist]

Large rifle primers have a taller, wider and thicker cap than small rifle plus more primer material.

Does it have any negative effect on accuracy?

 

[Local Loader]

Does it have any negative effect on accuracy?

Sorry, missed the past about switching brass.
Yes it will have an effect on accuracy as it will change the burn rate by either being to light or to hot for the powder that's used. As you said, you'll have to work up a new load for your round. Some choose to change powders when they change primer sizes but that's up to you.

 

[JuglansRegia]

They came out with small primer brass for 308 6.5cm and others because people believe it offers an accuracy advantage. So they "should" shoot better but you know how that goes.

 

[DizzyJ]

If'n yer will'n to play with the load I'm sure you will be able to achieve acceptable accuracy.

 

[Chaffee]

Look at the .308 Palma loads, they use small rifle primers on the 155 g AMAX, and in the team Savage youtube video from shot show they claim a 4" group at 1000 yds??? Out of the 30" barrel. I picked this up a couple of months ago, so I did a little research, but my range here is limited to 400 yards, so it's never been out of the box. I did look for the small rifle primer brass, but didn't have much luck. I did find that Lapua makes it.

 

[Local Loader]

Look at the .308 Palma loads, they use small rifle primers on the 155 g AMAX, and in the team Savage youtube video from shot show they claim a 4" group at 1000 yds??? Out of the 30" barrel. I picked this up a couple of months ago, so I did a little research, but my range here is limited to 400 yards, so it's never been out of the box. I did look for the small rifle primer brass, but didn't have much luck. I did find that Lapua makes it.

View attachment 1394600

Starline makes 308match brass as well which use srp.

 

[ddjchemist]

I already got 308Win Lapua brass with small primer pockets. I purchased it last year and so far never used it. I still have over 1,000 Fed M210G LR match primers. After I spend them, I guess I will move to small rifle primers. MidwayUSA had yesterday Fed G205M small rifle match primers and I was able to buy two bricks (2,000 primers).

 

[Local Loader]

I already got 308Win Lapua brass with small primer pockets. I purchased it last year and so far never used it. I still have over 1,000 Fed M210G LR match primers. After I spend them, I guess I will move to small rifle primers. MidwayUSA had yesterday Fed G205M small rifle match primers and I was able to buy two bricks (2,000 primers).

How much was the hazmat & shipping?

 

[ddjchemist]

$22.99 for hazmat shipping

 

[ddjchemist]

I just checked MidwayUSA website and Federal G205M small rifle match primers are still available.

 

[Local Loader]

Not sure how you got 2 from Midway since they got a 1 brick limit. I know Natchezss has them available by the case.

 

[ddjchemist]

That what friends are for. One I got and another one my friend ordered for me.

 

[Local Loader]

Ah, well if you need more natchezss let's you buy them up to 10 Bricks at a time.

 

[ddjchemist]

Ah, well if you need more natchezss let's you buy them up to 10 Bricks at a time.

Yes, I am ordering from them now another 1K brick.

 

[rhollister71]

Ah, well if you need more natchezss let's you buy them up to 10 Bricks at a time.

And unlike Midway will ship mags to Oregon. i have boycotted Midway until they back us here in Oregon. sad cuz i like there pricing and availability

 

[ThePants]

Does it have any negative effect on accuracy?

Starline does not indicate impact on accuracy. In fact they call starline 308 small primer pocket brass "match" grade. They do however state care needs to be taken:

"*As with all types of cases this large with small primer pockets, it will require care in powder and primer selection in cooler temperatures to prevent hang fires. Single-based propellents are generally easier to ignite and a quality primer such as the Remington 7 1/2 BR are recommended."

308 Match Brass - Small Rifle - Brass Cases