Is this normal?
So, I am reloading for a new Winchester 70 in 25-06. Looking at several different reloading manuals, for 115-120 grain bullets, a lot of them are listing an OAL of anywhere from 3.155 to 3.250. Specifically, for a 120 grain flat base, Spitzer bullet, the OAL is 3.250. Using my hornady OAL guage, I'm getting a max OAL of 3.130 to the lands. My question is whether more rifles than not are short throated like this. If I'm not mistaken, this throws the reloading manuals off, because pushing the bullet deeper than the manual gives will increase pressure. I experienced this doing my load work up. I'm seating this particular bullet .025 off the lands for an OAL of 3.105, and at 48.0 grains of R-17, that is 2 grains under their given max load, my primers are way flat, definitely showing signs of high pressure. If I could get some opinions or insight into this, it would be appreciated. Thank You
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The ogive on the bullet can vary over time as the design changes and that just one make. Every brand is different. That's why they tell people to start at the starting load and work up. I'm sure the throat will wear some very quickly. Some primers are tougher than others and don't show pressure as well. Flash hole size affects pressure. 0 -
Don't pay any attention, to the loading manuals. You are doing the correct thing, by using the OAL gauge. To check headspace. Drop back a couple more grains. For safety sake. Work slowly up from their, if the primers look OK. 0 -
Long ago in my reloading days, for many bolt action rifles I found that the best accuracy was obtained when the OAL was such that the bullet was almost touching the rifling.... virtually no bullet jump before starting to spin. Of course the OAL used depended on the shape of the bullet I was using and it also varied from rifle to rifle as there could be considerable variation in the throat length even within the same make and model. Things may be much more uniform these days. 0 -
I dropped back to 47.0 grains of R-17 from 48.0. Velocity went from an average of 2999 to 2886. ES and SD both dropped as well. With 48.0, ES was 31 and change and SD was 16 and change. With 47.0, ES went to 17 and change and SD dropped to 9 and change. Primers look more normal, but I'm still getting a pesky flier. On a 3 shot group, 2 shots will be @ 1/4" apart, and 1 shot will be approximately 1" away. Haven't got that figured out yet. I had won an auction here on gunbroker for 400 Sierra, 117gr bullets for $30. What a deal right? Wouldn't you know it, they are lost in the mail somewhere. Probably won't get them. Dang! So, I'm trying to get these speer 120 gr. hot cor's to shoot. Well, I'm getting 2 out of 3 to shoot good. Just have to figure out the flier thing. 0 -
" I'm getting 2 out of 3 to shoot good. Just have to figure out the flier thing."...........SIMPLE, JUST DON'T SHOOT THE 3RD ONE 
. BARREL HEATING MAY BE DOING THIS.0 -
Mike Whiskey. Good point. That's funny. Heck, never thought about that. Too easy. LOL 0 -
I found a few instances where the "suggested" OAL produced interference between bullet and lands. Some really accurate ammo but once in a while the bullet would pull when unloading and unfired round. I went back and seated about 80 rounds a little deeper to prevent this and all is well. 0 -
hadjii,
To me it sounds like you're measuring Base-to-Ogive, NOT OAL. But I could be wrong...
OAL can be measured with calipers from the base of the case to the very tip of the bullet.
BTO is measure using an adapter on your calipers to go over the nose and rest on the Ogive just above the full diameter of the bullet. This automatically gives you a shorter measurement because the tip of the bullet is inside the adapter and the calipers measure from the point of contact on the Ogive.
If you decide to use OAL just use the regular caliper blades and set your length to the book length.
Best.0 -
Nononsense I'm definitely measuring from base of bullet to the tip, not the ogive. I have the adaptors for measuring base to ogive, but more often than not, I don't use them. Just easier to measure from base to tip, at least for me. I'm not sure what to think of this Winchester 70 yet. I've tried 4 different bullets and 4 different powders, and so far, my ruger no 1 in 25-06 is beating the pants off this Winchester 25-06, and that, to me is just unfathomable.
The 4 powders I've tried so far are ramshot magnum, H4831SC, Reloader 17, and IMR4831. The 4 bullets are 117 gr Sierra gameking, speer 120 gr hot cor, Remington 115 gr ultra-bonded, and just starting to work with 110 gr nosler accubonds. The best load I've had was 59.5 gr of ramshot magnum behind the 115 gr Remington @ .875" for a 3 shot group, but the primers were so flattened that they were mushrooming, and I thought the heck with that. Way too much pressure for me. I've had several groups that had 2 of 3 shots @ .5-.75", but inevitably 1 shot was anywhere from 1" to 2.5" away. I'm not getting that figured out very well. The simple answer is shooter error, but I doubt that's the answer when I can take cheapo federal blue box factory ammo and put 3 shots into a .75" @ 100 way more times than not.0 -
Pull the bullets, from the Federal ammo. And substitute your bullets, with the same overall length. Being sure, the ogive doesn't touch the rifling. See if the flyers persist. Or you might be able to buy the Federal bullets, to load using your brass and powder. Gotta be some reason your having flyers from your loads. And not with the Federal commercial ammo. 0 -
"Pull the bullets, from the Federal ammo. And substitute your bullets, "
Some folks do that BUT it violates several rules of reloading.0 -
OK, so this morning I did a head to head test between R-17, H4831SC, and Ramshot magnum powder, using the 110 grain nosler accubond bullet, seating all 3 to 3.220", which is .030" from the lands. Primer was federal 210 large rifle primers. For powder charge, I looked at nosler reloading manual, and used the middle of 3 powder charge listings for all 3 powders. Theoretically, keeping all things as equal as I can. For ramshot magnum, that was 59.0 grains, for R-17, that was 47.5 grains, and for H4831SC, that was 49.0 grains. Primers all looked acceptable for all 3 powders, so pressure was good. 3 shot groupings were as follows: ramshot magnum 2 3/8". R-17 15/16", and H4831SC was 1 1/4". Not really any fliers with this bullet, but the ramshot magnum definitely ain't working. H4831SC was ok, I guess, and the R-17 was a bit better. I think I'm just gonna settle for the R-17 load, and call it good. I have too many other things to do to keep fiddling around. Thanks for your help people. 0 -
I've had a few guns over the years that even though the twist rate was in the correct range, they just would not shoot a certain grain weight. Perhaps yours is one of those. 0 -
Bambihunter, I'm inclined to think you're correct....unfortunately. It shoots good enough for hunting, obviously. Just don't think it shoots as good as I think it should, considering the work I've put into it. It'll be alright tho. 0 -
All bullets in a given weight range are not equal . If the problem is consistent with the same brand bullet perhaps it is time to change brands . . I have owned a few guns that grouped great with noslers partitions and ballistic tips , shot decent with Speer and Remington corelocks bullets and shot patterns with everything else I tried Worth a try 0
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