Magazine length questions

[pburton]

So, I am sure that this has been covered before, but I am unable to find what I am looking for.. I am getting ready to build a new rifle and need a little help. Most of the parts I already have figured out. I am building a 300 wm and want to be able to run long bullets, seated out, and still run a repeater action. I don't think I can run Berger 215's out of a standard magnum box mag without seating them deep in the cases. I would prefer to run a BDL style bottom metal, but I am not against running a detachable mag system. I will be going with a Lone Peak Razor TI action, Rock Creek #5 fluted barrel finished at 28". Please provide me with some suggestions for extended box mags or detachable mag systems that will work for me. Thanks!

 

[codyadams]

Not sure what your throat will be like, but I'm doing some load development for my buddies rem 700 LR in 7mm rem mag, and the remington factory mag box is 3.695", you could run rounds as long as 3.680 with no issues, but again it depends on your throat.

PTG makes extended mag boxes, that's where I would look. I have heard bad stories about PTG's customer service though, so if you want one of their products, you may think about ordering it from somewhere else that sticks their stuff. I ordered their bottom metal from mile high shooting.

 

[jimbires]

Wyatts makes extended mags , and detachable mags .

WYATT'S OUTDOOR, INC.

 

[codyadams]

If you go with a detachable mag, I wouldn't get a wyatts drop in, they have a proprietary magazine design and are very long if you want a 10 round. If you want a DBM I would get one of the many that are AICS compatability type bottom metal. I got a wyatts for my short action, and while it is a quality piece, and worked very well, I can only get wyatts mags, and they don't allow as long of an OAL as the aics mags, and you can get a 10 round mag that is alot shorter (out the bottom of the rifle) than the Wyatts. The only benefit with the Wyatts drop in is that you don't have to inlet your stock for it. The Wyatts DBM also costs more than some of the other AICS compatible bottom metals.

Just my $0.02....

 

[FEENIX]

So, I am sure that this has been covered before, but I am unable to find what I am looking for.. I am getting ready to build a new rifle and need a little help. Most of the parts I already have figured out. I am building a 300 wm and want to be able to run long bullets, seated out, and still run a repeater action. I don't think I can run Berger 215's out of a standard magnum box mag without seating them deep in the cases. I would prefer to run a BDL style bottom metal, but I am not against running a detachable mag system. I will be going with a Lone Peak Razor TI action, Rock Creek #5 fluted barrel finished at 28". Please provide me with some suggestions for extended box mags or detachable mag systems that will work for me. Thanks!

IIWY, I'd work very closely with the gunsmith who is going to build the rifle for you, unless you're doing it yourself, for best fit of all components esp. not knowing what your rifle stock (this may or may not affect your options) is going to be. That is exactly what I did on my last custom build except I acquired all the parts before hand. I went with a chassis so all I needed was which magazine best suits my wildcat cartridge build.

If it is not too late, make sure you have a 1:9" for the recommended optimum twist for the 215s.

BTW, an excellent choice on chambering. Good luck on your build.

Cheers!

 

[sable tireur]

pburton,

I have used an OAL 3.650" for many of the long action cartridges and the longer VLD bullets without problems in the M700 magazine boxes.

If you have decided to use a Remington M700 for the basis of your rifle, you have it made without having to jump through any hoops. The long action comes with a long magazine box which will accommodate the 300 Win. Mag. case plus the Berger 215 Hybrid seated properly in the neck of the case. This also allows for adjusting the OAL if you decide to try to chase the lands as your throat wears.

If you decide that you really want the longer VLDs then you can switch to a DBM system and use Accurate Mags which run all the way out to 3.850" but will need their system or a chassis which accommodates that length mag. Otherwise, you can use standard AI mags set up for CIP length cartridges and limit the length to 3.750" which do not use the spacer in the mag.

Work this through with your gunsmith as he will have the information about the ideas you may want.

Regards.

 

[pburton]

Thank you for all of the responses. This gave me a few things to think about. I have a 300wm that I had built off of a R700 a few years ago. It was built to be a light weight, pack around the mountains rifle. I went and measured the throat on this rifle, since the gunsmith that built this one will most likely build the next one. And with that I assume the same reamer will be used, unless I specify otherwise. It looks like I could easily run the 215's in a factory Rem box mag without much problem. I should have looked at this before starting this thread. Although, I did not think about the fact that Berger recommends a 1:9 twist for this bullet. Glad I have not ordered the barrel yet.

The main reason for starting this thread though, was to make sure I did not over-look any potentially limiting factors with this build. I don't want to have to worry about not having enough magazine length to get the best possible performance out of this rifle. I have the opportunity to build to full custom rifle and want it to be perfect.

Thanks again for all of the responses, it has helped greatly!

 

[6point5x284]

I agree, talk to your gunsmith. There are extended box magazines if running a BDL setup that can get you all the way up to 4.00" internal mag length. I run a .300 WM (see signature) with 215's and have I think the Wyatt CFE-9 box which gives me 4.00". Plenty of room for my 215's. I can actually seat the 215's all the way out until they would fall out of the case and still fit in my box. Also, the 215's and Hybrids in general are much less finicky with jump than the VLD's. I still seat a couple thousandths off the lands because I have the room and it shoots well there, but if I backed it off and had a decent jump, I am quite confident it would still shoot great. That's one of the bonuses of the Hybrids is you don't necessarily NEED that long mag length.

You mentioned barrel twist. Mine is 1:10, and many others. Berger when the 215's came out recommended 1:10 so there was a lot of 300's built on 1:10. I don't know anyone who has had issues stabilizing with their 1:10. Look at Bergers stability calculator, and you can plug in your numbers for your load and elevation, etc... and it will tell you if you are stable or not. I'm very much in the center of stability with a 1:10 and my 215's. If I bumped up to the 230 I'd probably have to take a closer look though.

 

[pburton]

I agree, talk to your gunsmith. There are extended box magazines if running a BDL setup that can get you all the way up to 4.00" internal mag length. I run a .300 WM (see signature) with 215's and have I think the Wyatt CFE-9 box which gives me 4.00". Plenty of room for my 215's. I can actually seat the 215's all the way out until they would fall out of the case and still fit in my box. Also, the 215's and Hybrids in general are much less finicky with jump than the VLD's. I still seat a couple thousandths off the lands because I have the room and it shoots well there, but if I backed it off and had a decent jump, I am quite confident it would still shoot great. That's one of the bonuses of the Hybrids is you don't necessarily NEED that long mag length.

You mentioned barrel twist. Mine is 1:10, and many others. Berger when the 215's came out recommended 1:10 so there was a lot of 300's built on 1:10. I don't know anyone who has had issues stabilizing with their 1:10. Look at Bergers stability calculator, and you can plug in your numbers for your load and elevation, etc... and it will tell you if you are stable or not. I'm very much in the center of stability with a 1:10 and my 215's. If I bumped up to the 230 I'd probably have to take a closer look though.

I ran the numbers through the Berger calculator and 1:10 twist would be fine since I live at 5000' and a majority of my hunting is at around the same of higher. My only concern is that from time to time I do have hunting opportunities come up in places that are far closer to sea level. This is where that calculator shows some borderline stability. Thanks for the info!

 

[6point5x284]

I ran the numbers through the Berger calculator and 1:10 twist would be fine since I live at 5000' and a majority of my hunting is at around the same of higher. My only concern is that from time to time I do have hunting opportunities come up in places that are far closer to sea level. This is where that calculator shows some borderline stability. Thanks for the info!

Ya, if I was building a new one today, I would go with 1:9. Just saying your 1:10 would still more than likely be just fine as well. The way the science is going, bullets are only to get longer and higher BC's anyway. Might as well posture yourself to have a barrel to run them as new bullets come out.

 

[FEENIX]

Ya, if I was building a new one today, I would go with 1:9. Just saying your 1:10 would still more than likely be just fine as well. The way the science is going, bullets are only to get longer and higher BC's anyway. Might as well posture yourself to have a barrel to run them as new bullets come out.

That's exactly why I had 1:9" 27" Lilja 3G on my latest custom build. IIRC, Hammer Bullet is recommending 1:8" on their .308 cal bullets.

ADDED:

Yep, they sure do >>> https://hammerbullets.com/product/308-cal-227g-hammer-hunter/