free bore?
 

How much free bore should a Remington 700 have? It is chambered in 7mm Ultra. I cant get the bullet close to the lands.

RE: free bore?
 

if the 7 Ultra is the same as the 300 ultra, you will not be able to get the bullet close to the lands.........you just basically seat your bullet so that it fits in your magazine and be done with it. Make sure you can fill your magazine and they cycle properly. example, my magazine in my 300 rum is 3.62" so I seat my bullets to 3.59 col.

RE: free bore?
 

So I guess this means rebarreling the rifle? I want to be able to seat the bulet close. Maybe have a reamer made to make it less. I have 3 7mm Ultras and 2 300 Ultras and this is the only one I am having trouble with. The other I can seat the bullet to where you cant close the bolts and the ammo will still cycle through the magazine

RE: free bore?
 

news to me.......if you can touch the lands, are you still keeping enough bullet in the neck?

RE: free bore?
 

yes, but with the one Im haveing the problem with I can seat it out to where there is no way it wi fit the mag and still cant touch the lands.

RE: free bore?
 

I went on this mission when the 300RUM's came out, I went out to gun stores with my stoney point and a few different bullets. Now, in most it appeared the 3.65" was too tight in the mag. so I would back them down to 3.62" max COL.

Shortest chamber I found, was with a 200gr swift a-frame and that was loading to 3.75". Most hovered around 3.82". Thats almost .2" of freebore. Not near like a weatherby but alot of freebore.

I know a guy who had a custom 300RUM built and he built it so he could touch the rifling and still put it in a 3.6" mag. He couldn't use any loading data whatsoever that was out there. And never did really achieve any groundbreaking velocity. So the actual freebore is needed to achieve some velocity. He couldn't even shoot factory ammo. So think twice before messing around with that freebore.

I have three RUM's and none could you get that close to the rifling and still fit in mag. One was a custom built one with a krieger barrel and done with a clymer reamer.

I highly suggest to not put so much emphasis on touching the rifling if its a hunting rifle. It will cause more headaches than anything. If have the need to be .002" from the rifling for target, I suggest the heaviest bullet you can find. I tried it with 200gr matchkings and it didn't do anything groundbreaking.

RE: free bore?
 

I load my 300ultra ammunition to 3.670" and they work well in magazine.At that length the bullet is .050" from the rifling in one rifle and .120" in the other.

RE: free bore?
 

Stubble which one do you see the best velocity performance and which one do you see the best accuracy performance or are they one in the same? Just curious.

RE: free bore?
 

The rifle where the bullets are seated at .050" produces 3380fps with 93gr of r-95 while the other rifle produces 3360fps with 88gr of a different batch of r-25.Accuracy with both averages 5/8".The bullet in both cases is the 180gr tsx.

RE: free bore?
 

I would love to know if its cause a different batch or the throat or tighter rifling.

I have seen different batches of RL25 react totally different but nothing as crazy as 5gr. I made up one accurate 180grTSX load in my old 300RUM with one batch at 89gr of RL25, and with a new one, never could get that accuracy out of it again. So I tried some left over ammo from the other batch and sure enough it was more accurate. Never did bother with working the load back up again with new batch. If I ever use it again, I plan to try to buy an 8lb container. But doubt it after those results.

RE: free bore?
 

I can't explain it either,but when I was using the 180gr ballistic points the powder charges were within 1 grain using the same two batches of powder and velocity was nearly identical as well.One barrel just seems to produce more pressure and velocity than the other with the tsx.Of course that could be a good thing since recoil calculations say that less powder burned for the same velocity does result in less recoil.As well burning less powder should reduce throat erosion slightlyas well.

RE: free bore?
 

It sounds like to me that Bigcountry needs to get another 300rum, heck you taught me everything I know about them and now you dont even have one. I think your next one should be a Savage! ;)

idaho elk, I hope we helped you with your problem.....maybe you could at least try and just load them to fit your mag and see how the accuracy is???

RE: free bore?
 

I am looking for another one. But wanting a sako 75 however.

RE: free bore?
 

you cant KEEP one unless it shoots better than mine!;):D

RE: free bore?
 

aol is 3.680 and cycles fine through the mag. I will just play around with it and see what it will do. Honestly I have given the rifle a chance. Just made upone load with 154 grain Interbonds and best groups were around moa. I have shot 3 animals with the IB's and will not be using them again. Thanks guy for the opinions and advice!!

RE: free bore?
 

I'm thinking that you should leave it alone there are reasons they do things like free bore , it has to do with presser and it that caliber their is allot of it .wetherbey has a similar configuration in their big bores.
about a year ago i spoke with a gun smith about changing a 300 mag into a 300 Ultra he said no as that they have a tendency to blowup

RE: free bore?
 

I think I would be finding another gunsmith. Cause that one is pretty well dead wrong. Pressure is pressure if its in a 22-250 at 60KPSI or a 300RUM. Only reason one might blow up is if they ignore the obvious pressure signs or don't work up a load. And they are not too bright if they do that anyway.

RE: free bore?
 

You definitely need to find a new gunsmith.The one that you talked to is an idiot.

RE: free bore?
 

I have a Sako 75 in 300 RUM. I found it on Gunbroker. A pawnshop in Montana had it listed. Blue walnut looked like new $750 It was listed 3 different times after I noticed it. I happened to run into the extra cash and got it. I cant figure out why it didnt sell before.

RE: free bore?
 

I have shot the gun and in all honesty it shoots beeter than I thought it would. My first load was 154 grain Interbond. 95.3 grains RL25 1 inch group. Now before you say anything about the load, I did work up to it and no visible pressure signs. I purchased some Barnes TSX bullets to try but cant find any data on them or any Barnes bullet for this caliber. I dont like the Interbonds or Accubonds as I havent had a pass thru yet. Seems like most people like to recover bullets and I am the opposite and that is all I have done since using them. But then again everything I have shot with the Interbond except a bear dropped in its tracks

Thanks guys for all the help. I posted on several different forums and this is about the only place I got any help. If I got help on any of the others it was a few of you and I really appreciate it.

RE: free bore?
 

Yep, I saw it on gunsamerica and gunbroker. It was a demo from Berreta here in MD. I called about it and decided I use 300RUM's for West or Canadian hunting. And everytime I go to Canada, usually I face some bad weather for days on end, and decided I wanted stainless/syn.

RE: free bore?
 

delete

RE: free bore?
 

ok so you guys kinda peaked my interest in the 7 rum, so I did some searching on gunbroker etc, and found some lefthands on there one was even locally that I have sent an email about. One very interesting thing though. Iknow the 7 rum is probably dying and lost some interest, but I could not find anything in my Nosler reloading manual about it. I mean they have 300 rum, 338 rum and even (IMO) the scarce 375 rum, but no 7 rum. Why would they not have anything about it, (they have 7 SAUM listed) ???????? Im perplexed!!! :D

RE: free bore?
 

I have seeen data only in 2 manuals. Hornady and I cant remember the other. When I purchased my first 7 Ultra Remington loaded 140 and 160 Nosler partitions for it. Now they only load 140 core loks. I dont even know if they still load the partitions in 140. The 160's shot hole thru hole groups. That made me fall in love with it. The only other factory gun I have that will do that is my 6mm Remington. I had a friend over on day that shoots really well. There was ground squirell on their monts and he shot 7 time over about an hour schredding 7 on them varnints. The shorted was 160 yars and the furthest was about 380. To this day evertime he comes up with a new gun he is over trying to swap me out of it.
I read inone the hunting magizines that most were afraid to give data on it claiming it was unpredictable to load for. I havent had any problems loading for them. Just trying to find data. The worse bullets I have used to date are the Interbonds and Accubonds. They dont penatrate enough to satisfy me

RE: free bore?
 

It looks as though the 7 STW is going to endure as the "Big 7" - despite the theoretical advantage of the 7 RUM case design.

RE: free bore?
 

I hope so. I got a dandy load for my STW, and still havn't got to get it bloody yet. And I bought a take off new sako barrel so I can burn this one out:D

RE: free bore?
 

You don,t want the bullet next to the lands!! vangunsmith

RE: free bore?
 

The 7 mag has always been known as the "big 7". The 7mm STW should be tagged "monster 7". I agree with your assessment. I also wonder how long the barrels are going to last in the RUM's? Regards, Rick.