Larger 7's for F-Class

[Joe R]

If the recoil was taken out of the equation, would there be a benefit to shooting some larger 7 MM calibers for Fclass. Take the 28 Nosler for instance, I hear about guys building 1/4" moa guns and if you could push the 195 to almost 3100 ft./s and have less time of flight, therefore having less wind drift at 1000yrds on windy days, meaning less margin of error! I would think the drift between the 28 and the 284 would be quite a bit! Been wondering what the recoil of a 22lbs 28 would be like! Is it a comfort factor with recoil that makes a lot of us shoot better! Obviously a lot of you guys have done this a lot longer than I, but I'm always trying to think outside the box, bad habit I guess! As always, your thoughts are greatly appreciated!

Seems that you have already chosen two variables, the bullet (Berger 195 class) and the velocity (~3100fps). Now all you have left to select is the powder that you want to burn. Buy yourself a copy of Quickload and start playing with it and it will help you narrow down which of the calibers you're considering has the case capacity to get you there. The QL numbers can also help you get an estimate of the recoil you'll be dealing with.

Once you have the caliber, you can run the numbers through the Barrel Life Estimator spreadsheet and you'll have a pretty good idea of what you're getting into and if it is is something that you can live with. That's the way I looked at it before building my 7mm.

It seems to me that the 195 & 197 class bullets are the new frontier and they are going to cause changes among the 7mm calibers.

Joe

 

[Elwood]

It has been my experience that the weakest link in 6.5 x 284 brass (what is used to make .284 brass) is the primer pocket. As a matter of fact Shiraz Bilolia, owner of "Bullets.com", spent lots of his $$$s to have Norma create "straight" .284 brass with the heads "double stamped" to help with the problem that .284 brass has with easily loosened up primer pockets. They surely are easily destructable.

I'm surprised by this as I have Shehane cases fired at possibly a faster speeds than most in the US, and have got 10 reloads, actually after tightening up the primer pockets with the Henry Rempel tool I'm now 12 firings.

Going back to the original question I'm surprised no one has mentioned the 7/270WSM or 7 WSM. This can quite comfortably push the 195 gr Berger to between 2950-3050 fps and when you run them at those speeds they shoot inside 4 inches against a 284 with the 180's doing 2830 fps, just a shame I couldn't get them to shoot!

 

[ShootDots]

I'm surprised by this as I have Shehane cases fired at possibly a faster speeds than most in the US, and have got 10 reloads, actually after tightening up the primer pockets with the Henry Rempel tool I'm now 12 firings.

Going back to the original question I'm surprised no one has mentioned the 7/270WSM or 7 WSM. This can quite comfortably push the 195 gr Berger to between 2950-3050 fps and when you run them at those speeds they shoot inside 4 inches against a 284 with the 180's doing 2830 fps, just a shame I couldn't get them to shoot!

I and several people I know that if you run anywhere near max with a "straight" .284 or a Shehane, we have loosened up primer pockets quickly. It has been a complaint large enough that Shiraz went to Norma to make straight .284 brass with the primer pockets "toughened up" so to speak.

Those other 2 "shortmags" are also excellent for the heavier 7mm pills. I have a 7mm SAUM I am currently working on. It appears at this stage to be very promising! I intend to shoot it at the TSRA (Texas Rifle Assn) long range state championship at Bayou Rifles in April. If early results stay the same, it should be an excellent performer. We shall see.

 

[TZaun]

I know this is about larger 7s for F-Class, but I too believe the Norma primer pockets open up too easily. I tried some in my 6.5x284 and they wouldn't last nearly as long as my Lapua brass.

I just had a new rifle built in a 7 RSAUM and it's throated to shoot the 195 Bergers. It will be my 1,000 yard F-Class rifle this summer. Hoping to get started on load development very soon. If it doesn't shoot the 195s like I'm hoping, I have 183 Sierras to try also. 8 twist, 30" barrel. Hopefully I can contribute some information on it someday soon. Going to start with N165.

 

[ShootDots]

I know this is about larger 7s for F-Class, but I too believe the Norma primer pockets open up too easily. I tried some in my 6.5x284 and they wouldn't last nearly as long as my Lapua brass.

I just had a new rifle built in a 7 RSAUM and it's throated to shoot the 195 Bergers. It will be my 1,000 yard F-Class rifle this summer. Hoping to get started on load development very soon. If it doesn't shoot the 195s like I'm hoping, I have 183 Sierras to try also. 8 twist, 30" barrel. Hopefully I can contribute some information on it someday soon. Going to start with N165.

With the 195's, N165 would be the fastest powder I would use. H1000 or RL-26 I think would be perfect. For the 183's N165 should be right on the money! I am presently using 180 Hybrids with H4831SC. But I want to try the 183's a bit later and I bought some RL-23 for that application. I also have some N165, however, the RL-23 is supposed to be SUPER temp stable!

 

[Elwood]

I and several people I know that if you run anywhere near max with a "straight" .284 or a Shehane, we have loosened up primer pockets quickly. It has been a complaint large enough that Shiraz went to Norma to make straight .284 brass with the primer pockets "toughened up" so to speak.

Those other 2 "shortmags" are also excellent for the heavier 7mm pills. I have a 7mm SAUM I am currently working on. It appears at this stage to be very promising! I intend to shoot it at the TSRA (Texas Rifle Assn) long range state championship at Bayou Rifles in April. If early results stay the same, it should be an excellent performer. We shall see.

Ben, I'm not disputing your facts, it clearly happened to you and a few others. I'm on my fourth Shehane barrel and second .284 barrel and haven't experienced what you have encountered, one of us has been lucky or unlucky.

 

[ShootDots]

Ben, I'm not disputing your facts, it clearly happened to you and a few others. I'm on my fourth Shehane barrel and second .284 barrel and haven't experienced what you have encountered, one of us has been lucky or unlucky.

I have some "old" "Gold Box" 6.5 x 284 brass that I turned into straight .284 brass. It has really tight primer pockets. I have had from BOTH "Pre-Shiraz" Norma and Lapua 6.5 x 284 brass that had fairly loose primer pockets with no firings, right out of the starting gate. All this leads me to believe that various lots of brass from both manufacturers have BOTH tight and loosely made primer pockets from the factory. I am glad you got hold of the tight ones! LOL!!

 

[TZaun]

With the 195's, N165 would be the fastest powder I would use. H1000 or RL-26 I think would be perfect. For the 183's N165 should be right on the money! I am presently using 180 Hybrids with H4831SC. But I want to try the 183's a bit later and I bought some RL-23 for that application. I also have some N165, however, the RL-23 is supposed to be SUPER temp stable!

H1000 is going to be my 2nd try at it, if the N165 doesn't work too well. What velocity do the 180s like to be shot at? I have a 9-twist barrel set up for the 180s, too, if my 8-twist doesn't like the 195s or 183s.

 

[ShootDots]

H1000 is going to be my 2nd try at it, if the N165 doesn't work too well. What velocity do the 180s like to be shot at? I have a 9-twist barrel set up for the 180s, too, if my 8-twist doesn't like the 195s or 183s.

So far I am getting 2965 with the Hybrids with 60.3grs of H4831SC. I believe you may very well get excellent accuracy with the 195's ahead of N165, however, I don't know if you would get past 2800 f.p.s. before pressure signs show up. But with H1000, I have 2 friends that are running 2875 with the 195's out of their SAUMs. BOTH of them are loading 61.1grs with H1000 under the 195's BUT they have .280 freebores, substantially more than most have in their SAUMs.

 

[dsbw]

I know this is about larger 7s for F-Class, but I too believe the Norma primer pockets open up too easily. I tried some in my 6.5x284 and they wouldn't last nearly as long as my Lapua brass.

I just had a new rifle built in a 7 RSAUM and it's throated to shoot the 195 Bergers. It will be my 1,000 yard F-Class rifle this summer. Hoping to get started on load development very soon. If it doesn't shoot the 195s like I'm hoping, I have 183 Sierras to try also. 8 twist, 30" barrel. Hopefully I can contribute some information on it someday soon. Going to start with N165.

I have never had any problem with any Lapua case, regardless of calibre, with loose primer pockets. 284 Win cases in particular were very good with primer pockets. I've never used Norma, have no idea about them, but on my 284 the Lapua brass pockets were indestructable.

 

[TZaun]

So far I am getting 2965 with the Hybrids with 60.3grs of H4831SC. I believe you may very well get excellent accuracy with the 195's ahead of N165, however, I don't know if you would get past 2800 f.p.s. before pressure signs show up. But with H1000, I have 2 friends that are running 2875 with the 195's out of their SAUMs. BOTH of them are loading 61.1grs with H1000 under the 195's BUT they have .280 freebores, substantially more than most have in their SAUMs.

Jeez, thanks a bunch for that info!! I'm moving to the H1000 to try first then. I don't know what my freebore is, but, I made a dummy round the other day and hard jamb puts the bearing surface/boat tail junction right in the middle of the neck.

 

[ShootDots]

Jeez, thanks a bunch for that info!! I'm moving to the H1000 to try first then. I don't know what my freebore is, but, I made a dummy round the other day and hard jamb puts the bearing surface/boat tail junction right in the middle of the neck.

It sounds like you have a good freebore. Just work up and don't start at 61.0grs and you should be fine.

 

[Alex Wheeler]

I have to agree with Ben. Primer pockets loosen up on Lapua 284 brass pretty easily compared to other cases. I think it has to do with the rebated rim. Larger case diameter=more bolt thrust, smaller rim diameter=more force on case head. I think personally I would try a saum next time and just take it easy, run 2850 with 180s.

 

[TZaun]

I have never had any problem with any Lapua case, regardless of calibre, with loose primer pockets. 284 Win cases in particular were very good with primer pockets. I've never used Norma, have no idea about them, but on my 284 the Lapua brass pockets were indestructable.

Apparently I was running pretty hot with the 139 Scenars, but that's where that barrel shot them the best. I could only get 4 firings out of my Lapua brass. I switched to the new Norma 284 brass to try them out and after doing load development again to verify where they shot great again (turned out to be the same load as my Lapua brass), I only got 1 firing out of my Norma. Had to Super Glue the primers in the 2nd time to shoot the last match of the season. 49.2 gr. of N160 was what I was using. My old Chrony said it was about 2960 fps. I was never sure if that was right or not. Sure shot good though.

 

[kyreloader]

So far I am getting 2965 with the Hybrids with 60.3grs of H4831SC. I believe you may very well get excellent accuracy with the 195's ahead of N165, however, I don't know if you would get past 2800 f.p.s. before pressure signs show up. But with H1000, I have 2 friends that are running 2875 with the 195's out of their SAUMs. BOTH of them are loading 61.1grs with H1000 under the 195's BUT they have .280 freebores, substantially more than most have in their SAUMs.

What twist are they using to shoot the 195s?

 

[dkhunt14]

I'm surprised by this as I have Shehane cases fired at possibly a faster speeds than most in the US, and have got 10 reloads, actually after tightening up the primer pockets with the Henry Rempel tool I'm now 12 firings.

Going back to the original question I'm surprised no one has mentioned the 7/270WSM or 7 WSM. This can quite comfortably push the 195 gr Berger to between 2950-3050 fps and when you run them at those speeds they shoot inside 4 inches against a 284 with the 180's doing 2830 fps, just a shame I couldn't get them to shoot!

In 1000 yard BR the 7 WSM was never very competitive. I believe it to be a little too much case capacity. I did see a few 7SAUM's shoot good. Matt

 

[Elwood]

In 1000 yard BR the 7 WSM was never very competitive. I believe it to be a little too much case capacity. I did see a few 7SAUM's shoot good. Matt

Matt, isn't the 300 WSM favoured in long distance BR? Is it a matter of a heavier projectile (200-230gr) matches the case capacity? I also thought I read that H4350 was often used with this combination? A powder that I have been experimenting with in the 7/270 WSM and 180's, I even had a play with it and the 195 Berger's!

Sorry if this taking the thread off topic.

 

[ShootDots]

What twist are they using to shoot the 195s?

They are using an 1-8.25 twist. The recommended twist is 1-8.30 but literally anything from a straight 8 thru a 1-8.5 works just fine.

 

[dkhunt14]

Matt, isn't the 300 WSM favoured in long distance BR? Is it a matter of a heavier projectile (200-230gr) matches the case capacity? I also thought I read that H4350 was often used with this combination? A powder that I have been experimenting with in the 7/270 WSM and 180's, I even had a play with it and the 195 Berger's!

Sorry if this taking the thread off topic.

Yes the 300 WSM is a favored one. I believe by going up to a bigger bore and heavier bullet makes it better. The case is full and the velocity is right. Lots of 6.5 WSM's AND 7 WSM's have been built and shot. None of them shot good enough to win regularly. Maybe the 7 with a 195 will work better. It just was too much capacity for the 180. The velocity seemed to be too high for the accuracy node. But BR and f-class have different requirements. Matt

 

[TZaun]

They are using an 1-8.25 twist. The recommended twist is 1-8.30 but literally anything from a straight 8 thru a 1-8.5 works just fine.

Ben, what primers, do you guys find, work best for the 195s and 180s? I've read that some guys get great results with non-Magnum primers in the SAUM. Wondering if that's only for the 180s and faster powder?? My gut says 61 gr. of H1000 would need a Magnum primer to ignite consistently.