Necking 30-06 to 25-06 results in blown primer

[Hugnot]

Here are SAAMI specs for the .25-06.

like most things variations from chamber to chamber might occur. The reamer should be made to SAAMI specs.

 

[B-LOT Banga]

@CBS the Berger 115's are no good for a 25-06, I can send you a packing slip and you can ship whatever you have to me.... you can thank me later.

In all seriousness I have some brand new 25-06 "Winchester" brass I can send you to see if you encounter the same problems. As other members have mentioned turning your necks will most likely solve your issues. But it wouldn't hurt to load some 25-06 brass up and send it. It would be the cheapest and easiest way to confirm or debunk your suspicions. PM me brother and I will get some brass out to you!! Aloha

 

[baldhunter]

25-06 is susceptible to pressure spikes.Burning a large amount of powder through that small bore is doable,but when it reaches it's peak pressure can really jump up quick.Reduce your load a grain or two and see if that helps.

 

[javman]

I've done it with 270 brass with no problems.

 

[CBS]

Guys, thanks for all the great info. My necks are indeed too thick. A 25 cal bullet will not slide into the spent case. I get to pull some bullets and learn to turn necks now. Or I might just go searching for 25-06 brass to save myself.

I really appreciate everyone's contribution to this thread!

 

[Mike Matteson]

I haven't had any problem with sizing 30/06 or 270 brass to 25/06. Sizing down if I remember correctly doesn't create a donut. (I could be wrong) If expanding the neck does create the donut. Somebody will add to this. The neck turning should be done before sizing down if going to be done. At the time in using other calibers to size to 25/06 I didn't cut necks. Case length will grow and that need to be watch all the time. I had a problem with one of my 25/06 years back. It was because of overall case length was to long. It will make it appear that high pressure from powder loads was to much, but it's case length. The neck being stuck in the chamber just a bit. Never had that problem again by checking my case length and keeping them trimmed. I am just about to pull the trigger on a Tri Trim Gen 3. Going to trim each time after firing the case. Another step I have or adding to my reloading.

 

[antelopedundee]

Guys, thanks for all the great info. My necks are indeed too thick. A 25 cal bullet will not slide into the spent case. I get to pull some bullets and learn to turn necks now. Or I might just go searching for 25-06 brass to save myself.

I really appreciate everyone's contribution to this thread!

I'd just get the .25-06 brass and be done with it. You may end up wanting to neck turn that anyway to get more uniform neck thickness.

 

[cabelasken]

I've found some brands of brass are significantly thicker than others and some are noticeably thicker on one side vs the other. You'll sometimes notice this when you neck turn your brass. I usually set my cutter to just trim up the high spots.

 

[Pointman]

Way back in the dark ages, there wasn't a lot of factory 25-06 brass available. In one of the shooting magazines, I found an article that using an RCBS 25-06 trim die you could "neck down" 30-06 brass successfully. Then after trimming to length with a fine file, chamfering the case mouths, and then running them back through full-length sizing dies you could produce brass was totally acceptable. The article did recommend fire forming the brass with low-pressure loads then working up to the desired velocity. I was able to procure a good quantity of Lake City military brass at a gun show for a reasonable price. The article also recommended annealing the necks, which was a chore using a butane torch and templaq marking. I used that brass for years before finally retiring them. My go-to load was 52 grains of H4831. It's still the load I use on that rifle.

 

[Hard rock]

Way back in the dark ages, there wasn't a lot of factory 25-06 brass available. In one of the shooting magazines, I found an article that using an RCBS 25-06 trim die you could "neck down" 30-06 brass successfully. Then after trimming to length with a fine file, chamfering the case mouths, and then running them back through full-length sizing dies you could produce brass was totally acceptable. The article did recommend fire forming the brass with low-pressure loads then working up to the desired velocity. I was able to procure a good quantity of Lake City military brass at a gun show for a reasonable price. The article also recommended annealing the necks, which was a chore using a butane torch and templaq marking. I used that brass for years before finally retiring them. My go-to load was 52 grains of H4831. It's still the load I use on that rifle.

My dad used to neck down to make 25-06 brass when it was a wild cat but now with the 2506 being a factory round I wouldnt waist the time with all the frustations get a 100 rds of brass and it will last you maybe the life of the barrel and the first firing will be in your chamber unless your necking down new brass just my humble opinion good luck

 

[KS2506]

First 25-06 was bought in 1966, custom FN with Douglas 1-12 twist match grade barrel. Necked down 500 30-06 match brass and started with 4831 and 100 grain Sierra bullets. No pressure problems even at 59.5 gr of powder, that was all the case would hold. On my 4th 25-06, never had any pressure problems with necked down 30-06 cases. Never reamed or turned any cases. Did you trim to length minus .010"? And BS on pressure spikes.

 

[Dean2]

I haven't had any problem with sizing 30/06 or 270 brass to 25/06. Sizing down if I remember correctly doesn't create a donut. (I could be wrong) If expanding the neck does create the donut. Somebody will add to this. The neck turning should be done before sizing down if going to be done. At the time in using other calibers to size to 25/06 I didn't cut necks. Case length will grow and that need to be watch all the time. I had a problem with one of my 25/06 years back. It was because of overall case length was to long. It will make it appear that high pressure from powder loads was to much, but it's case length. The neck being stuck in the chamber just a bit. Never had that problem again by checking my case length and keeping them trimmed. I am just about to pull the trigger on a Tri Trim Gen 3. Going to trim each time after firing the case. Another step I have or adding to my reloading.

You have it backwards. Necking up thins the brass, necking down tends to thicken it. Forming donughts in the brass is a ring INSIDE the neck near the shoulder. This can be casued by necking down, but it is also possible for these to form just from regular sizing of brass. You need to measure to find them, if they are there ream them out with a neck reamer. If the brass in the neck itself is over .014 you will likely need to turn the OUTSIDE of the neck. Aim for .013, but not less than .012 or you will need to use bushing dies to size them..

 

[jimwest]

I had a Remington action rebarreled to 25-06 because I have ample 30-06 brass hoping to resize and shoot. This is supposed to be a kids gun with low recoil with the addition of a brake. It hasn't been that easy. Resizing leaves a donut that will still chamber stifly. apparently the chamber pressure is high enough to blow a primer about 3-4 gains under my expected max load.

Questions:
- do I need to fire form the brass before working up a load? I was hoping to avoid this.
- is my powder just too fast?
- could my necks be too thick?

I'm using 115 berger, rl26, in a 10 twist barrel hoping to get it to stabilize. I'm nowhere near the lands.

I don't want to waste time and precious supplies trying to reinvent this wheel. I'm hoping for some experience to let me know which direction to head from here.

To all and for CBS,

Help me understand this in simple terms. The 'mass' of brass in the neck of a 30-06 case is greater that that of the 25-06. So, it seems to reason that you are going to have some excess brass after sizing down ( the donut). Thus, the need to turn, and then possibly neck size once again. This would depend if you were sizing with an expander ball and sizing from the inside or a bushing sizing from the outside. Regardless, wouldn't it be prudent to anneal the brass beforehand, thereby having more malleable/ductile brass that would cause less stress on the sizing process?

 

[ericbc7]

I like my 25-06 with light bullets but I don't consider it "light" recoiling. It is not as harsh as my 30-06 with 180 gr spitzers of course, but a recoil sensitive shooter will struggle with it.