|
|
|
Discussion Forums
Forum Index
> Precision long range hunting and shooting
> .30-06 Springfield 150gr Hornady SST load
.30-06 Springfield 150gr Hornady SST load
@ 07:45 pm (GMT) |
Drew PigottHello,I have a 2010 Weatherby Vanguard .30-06 Springfield. It has a bedded Bell and Carlson Meadlist stock an a "turned" 2-1/2 lb factory trigger, along with a 3-9x40 Leuplold VX1 scope. I am new to reloading but so far have been moderately successful in my load development. I'm using Hornady brass, from my rifle, Federal Large Rifle Match Primers, Hornady 150gr SST (right size for the animals I hunt) an Hogdon H4350. I am loading fifty thousands off the lands at a COL of 3.253". My problem is that I am printing two shots at around a half min apart an one that flys out, usually at 2:00, about anywhere from 1-1/2 to 2" from the others. It's very frustrating, an it's not a one time occurrance as it has happened around 10 times now. I've shot several slightly sub .75 MOA 3 shot groups so it leads me to believe its not the weapon or me.. During my seating operations I have noticed that some of the bullets are MUCH easier to seat. I have also noticed that my velocitys are all over the place from group to group, an day to day. My velocitys are ranging from around 2,980 - 3,080 fps with 60.3 gr of H 4350. Some of the groups have as little of spread as 4 fps to about 23 fps. I believe it's again due to my neck tension issue. I use a Forster Ultra Micrometer seating die an a RCBS neck sizer. Should I invest in a bushing neck sizer die to help with consistent neck tension? I've been looking at a Forster bushing bump neck sizer die. Or do I have it all wrong? Also, any thoughts on case neck turning? Thanks, Drew |
Replies
@ 09:13 pm (GMT) |
Jim MoseleyRe: .30-06 Springfield 150gr Hornady SST loadHave you checked the torque settings on the bedding screws? Your stock maybe loose. |
|
@ 10:03 pm (GMT) |
Drew PigottRe: .30-06 Springfield 150gr Hornady SST loadI just did. I don't have a torque ratchet but it seemed to feel identical.. |
@ 10:32 pm (GMT) |
Nathan FosterRe: .30-06 Springfield 150gr Hornady SST loadHi Drew, yes thats enough to drive anyone nuts.OK, lets get to it: Rifle variables: If the lugs have not been lapped, I can pretty much guarantee only one locking lug is touching, direction of thrust off center to the bore. Solution, lap lugs. Check the bedding is not pinching the action in place, especially at the recoil lug. Many smiths have a poor understanding of bedding- critical points of contact versus critical points of relief, there are even entire aftermarket companies who do not understand critical relief. The aftermarket tight fitting recoil lugs for Tikka T3 rifles are an example. I have put guides to inspecting your bedding job / rifle in the long range hunting book. King screw tension as Jim said- 55 inch lb on an ali chassis would be ideal (but not critical). Bore, please tell me about the rate of fouling. Please study the barrel break in article. Scope base should be glued and screwed as per the long range hunting book. Screws need to be thread locked in place Hand loads: Please address all of the above before looking at hand loads. I wouldn't mind if you would try experimenting at a COAL of 3.200. You'll note the cannelure of the bullet will be just inside the case mouth. The trouble with the current COAL is that not much bullet parallel is in the case, only .255". I want you to try and seat just past the cannelure, giving the bullet body about .315" bearing surface in the case mouth. The reason why some cases are tight necked and others are loose will be due to some cases being soft and others work hardened. Annealing is optimal but I think before you do this, yes you need to look at neck tension. If the die has an expander button, it may be opening the case necks up too wide. The button most likely needs sanding down (mounted in a drill). If you want to experiment without sanding, size and decap all of your cases, then remove the expander assembly and size them again without the button at all. This interim test may prove helpful. Neck tension will effect velocity and ES a big deal. The tighter the better in my book. H4350 is a temperature stable powder. In welter weight barrels, after a high round count on hot days, velocities can increase by 75fps- but this has as much to do with constriction of the bore. If you were starting out, I would recommend Varget for 150gr bullets but it sounds like you are up in the zone regarding velocities. Chronographs will give different readings in different weathers and also are susceptible to orientation such as north south versus east west. Best days for readings are overcast days. make sure the chrony is set at its recommended distance from you- no closer. repeat this distance each session. What you are going through is frustrating- yet entirely normal. Sometimes it can be fixed, other times it is a case of binning the barrel. For now, all you can do is go through the steps. I hear you. You have a lot of work to do, good luck. |
|
@ 10:48 pm (GMT) |
Nathan FosterRe: .30-06 Springfield 150gr Hornady SST loadOne other very important rifle variable Drew-Please check that the magazine box is not pinched in place. Drop the floor plate (rifle assembled) and try to wriggle the mag box. If it wriggles- good. if not, its either pinched from assembly or was pinched during bedding, requiring either alteration of the mag box or rebedding. Assembly pinching is very common on this rifle. careful reassembly is the key. |
|
@ 02:16 pm (GMT) |
Drew PigottRe: .30-06 Springfield 150gr Hornady SST loadNathan,Thank you very much for the extremely helpful information! I broke the rifle in in a similar manner as you described in your article. Now, the rifle had about 40 or so rounds down range since the last cleaning. Most of the apparent fouling was on the leading edge of the rifle lands. I cleaned it this mourning with Hope's #9 bore solvent his mourning in the same manner in which you spoke of in the barrel break in article. The lands came about 90% clean compared to what they were, pretty well fouled. In between the lands there is still a fair amount of copper fouling. I may have to break out the scotchbrite as you said. Anyhow, the H 4350 is burning pretty dirty too, with a distinct sulphur smell, not like the gunpowder I'm used to, I don't know if that even makes a difference.. I can pick up some Varget to try at my local retailer, they also have IMR 4064 an H 414 as I've heard they are also good for 150gr .30-06's. I have some Reloader 19, but don't know how that would work.. On inspection of my locking lugs I believe you are right on! From the top of the rifle the left lug shows a considerable amount of paint an wear compared to the right lug which has virtually zero wear. Is lapping the lugs something I can perform myself or do I need to take it to my smith? I've heard of headspace problems if you lap to much.. I also preformed the bedding check as you mentioned in your book (great read), my stock passed. Magazine is able to be wiggled with the floor plate released an the barreled action doesn't climb out of the stock when the front screw is backed of an then tightened. Thank you for the tip on the seating depth an neck tension. I removed my de-capping pen an resized 12 cases. They all run very close to .330 outside diameter now with as little of variance of .0005 thousands. Before they were running from .334 to .330. Which is huge.. I will shoot these most likely tomorrow an get back with you as to how it preformed. Thanks again Drew |
|
@ 04:32 pm (GMT) |
Nathan FosterRe: .30-06 Springfield 150gr Hornady SST loadOK, all of the copper needs to come out before any form of bore lapping can be performed. In this instance, I am hesitant to recommend abrasives as the solvent you used was very mild.Use Boretch or Sweets, swab the bore with a bristle brush and keep applying fresh solvent. Re check bore after about 10 minutes work. If the copper came away easily, there may not be any need for abrasive lapping. If the fouling was still very stubborn, then it is time to have a look at abrasives as described in the break in article. I am glad you had a copy of the book for bedding inspection, that makes life a lot easier. Looks like the bedding is sound, mag box sound, thats great. H4350 is cleaner burning than other brands. Cross contamination can cause problems. Not long ago, I came across a farmer who was hand loading in his work shop, a worker must have spilt a chemical nearby or something- we'll never know because he gapped it. Result, even trying to kinetically pull loads superheated the cartridge and caused ignition- bloody scary. If you want to try Varget, go for it. I find 4064 to be identical in every way. Lapping of the bolt lugs is sometimes best left for a smith in the off chance that a burr is picked up on the lug rebate (can gouge the lugs). I have sent you an email with DIY instructions. Don't worry about head space. As long as you neck size, this will take up any slack. Its no different to fire forming a wildcat. The job has to be done whether you do it now or wait till its time for a new barrel. |
|
@ 05:21 pm (GMT) |
Drew PigottRe: .30-06 Springfield 150gr Hornady SST loadNathan,Wonderful! Thanks for the help. When I get the lugs lapped an have tested the new data I will post my results. Again, thanks for all te help an God bless! Drew |
Please wait
ABOUT USWe are a small, family run business, based out of Taranaki, New Zealand, who specialize in cartridge research and testing, and rifle accurizing.
|
KNOWLEDGEBASE |
KNOWLEDGEBASE |