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View Full Version : actual chrono speeds of a 270 wsm?


kilotanker22
November 7, 2012, 06:23 PM
Hello all I just bought a 270 wsm in a new haven production model 70. That being said I bought some Winchester 150 grains power point ammo. Wondering if anyone has chronoed this ammo in a 24 inch barrel. Or any other factory 270 wsm ammo. And if so did it live up to the posted velocities.

Thank you for your replies. O and by the way are most model 70 rifles tight chambered?

Brian Pfleuger
November 7, 2012, 06:50 PM
Well, I'll have to tease you a little bit... I just so happened to have recently had a Savage 11, chambered in .270WSM and it just so happens that the only factory ammo that it ever shot was 150gr Winchester and it just so happens that I did, indeed, fire that ammo over a chronograph and it just so happens, that I have no recollection of the speed. :eek::o:D

Anyway, it won't matter much. Unless someone else's chamber was cut with the same reamer as yours, the speeds won't have much relation.

Most factory ammo doesn't reach published specs, the particular exceptions I've found are 17HMR and 7mm-08, for whatever reason.

kilotanker22
November 7, 2012, 07:15 PM
Thanks brian what part of southern central new York you from? I am from north central Pennsylvania. Not far from elmira.

By the way how did that ammo shoot. I have noticed that the quality from Olin corp ammo has been questionable as of late.

Brian Pfleuger
November 7, 2012, 07:20 PM
I'm in the Village of Lisle, between Cortland and Binghamton.

I got a group around 1 1/2 inches at 100 but I only shot 5, maybe 6 rounds, and only a 3 shot group. The rest of my shooting was mild handloads and not much of those.

Wyosmith
November 7, 2012, 08:07 PM
I have a Benelli R-1 in 270 WSM and I shot one box of Winchester factory 150 grain ammo through it. It shot about "modified choke".
I was appalled at the size of the pattern. It was fully 7" across and 6” tall at 100 yds.


I started testing hand loads in it and found that most would do about 3 MOA. However I found a sweet spot with a 160 grain Nosler bullet, and 66 grains of H1000. That load holds just over MOA with 4 shots. (Capacity of the gun when fully loaded)

It’s not an MOA gun, but it’s fully capable of being a good all around hunting rifle with that load. Deer and elk are big enough that I can get by easily with 1-1/4” accuracy.

Bart B.
November 7, 2012, 08:21 PM
Fellas, note that most factory ammo's tested in fixed barrels that don't move in recoil. Oft times, they are SAAMI spec'd for bore, groove and length dimensions. Those test barrels typically shoot a given factory load 50 to 75 fps faster than what the factory's rifles (with typically bigger bore and groove diameters) shoot them out at when hand held by consumers.

2ndtimer
November 8, 2012, 08:33 PM
Well, I tested the factory Winchester Power Point 150 gr loads in my then new Winchester Super Shadow .270WSM back around 2004 or so, and if I recall, they tripped the skyscreens at just over 3100 fps. The accuracy wasn't great, around 2" 3 shot groups at 100 yards from the bench. Subsequent handloads with Vihtavuori N-165 and Nosler 140 gr Accubonds matched the velocity of the factory 150's and grouped well under an inch at 100 yards. I suspect if I chronographed those factory loads today (I still have most of a box at home, maybe I should try it) I would bet they won't break 2900 fps. A slight bit of throat erosion.... But I bet my brand new unfired .270 WSM Model 70 Ultimate Shadow will!

Freakdaddy
November 8, 2012, 09:27 PM
I have a Winchester Featherweight in the 270 WSM out of New Haven. I haven't tested a wide variety of ammo through it (cost) and I don't reload as of yet. I also don't have a chronograph so I can't help you there either. What I have found is mine seems to like the Federal 140gr Nosler Accubond round and I if I do my part, I can put all 4 rounds (gun capacity) in under an inch. The most I've ever done was nine rounds in under an inch in a consecutive string and the other three opened it up to 1 1/4". Of course, I did have my trigger adjusted down to around 2 lbs. and have since increased it to around 3 lbs. Regarding the chamber, I don't notice mine being excessively tight but I do remember the action being a little stiff when new which is mostly typical of any mass produced firearm. It's very smooth now but not sloppy by any means.

Mine also seems to prefer a somewhat clean barrel. I probably had over 100+ round through it with doing nothing more than using Hoppe's #9 solvent for cleaning after each outing unless I was going hunting. The groups started opening up to 3" or more and was causing me all kinds of frustrations especially after getting the aforementioned groupings. Last year, I bought some Butch's Bore Shine and couldn't believe how much copper residue the Hoppe's was leaving in. My groups shrunk back down to 1" and under after that. For whatever reason, it seems that it takes around 10-15 rounds to get the gun settled back in after cleaning it this way but even these groups aren't more than 1 1/2" to 1 3/4". In all honesty, it may be more of a situation of "me" settling in as I don't shoot it that often and usually only when checking it before deer season starts.

The only other round I've tested in it was the Winchester 130gr Ballistic Silvertip but it's been quite a few years back and I don't remember the actual grouping from them but I do know the Federal's shot much better. I've often thought of trying more variety but I have to catch myself and ask why since this load seems to do extremely well through it and since I don't reload, hard to justify spending $150-$200 in various ammo to find something that's going to give my 1/4" tighter group. After all, this isn't a benchrest rifle, it's a hunting rifle and other than decreasing the trigger pull is straight out of the box. I've only had a couple of deer run after being shot and that was only for 40 yards at the most, all others have dropped right in their tracks. The longest shot I"ve ever made was with this gun and it was just shy of 400 yards and she only ran for about 30 yards before dropping. I have been very pleased with this bullets performance and although pricey, I think it's worth your time to get a box or two and try it out.

Freakdaddy
November 8, 2012, 09:31 PM
LOL! I had the reply window opened typing my response earlier and got busy doing other things. I see you knew about the Accubonds about an hour ago :D.

kilotanker22
November 9, 2012, 12:33 PM
Thanks for the replies all. I went to the range yesterday with the gun and was getting around two moaning with five shot groups. But I did get several time three shot groups hovering at one inch. That was with a 9 power Nikon.

I guess my real question should be should I expect a 50 to 100 fps reduction compare to advertised velocity? I don't have a chrono and don't know anyone with one. By the way even at 100 fps less than posted that is still 3050 fps. Compared to a 270 with 150 grain factory advertised at 2850.

jmr40
November 10, 2012, 07:11 AM
There is no way to know for sure without a chronograph. I've found that in most cases I get pretty close to the advertised velocity, sometimes a little faster. The key is barrel length. If your gun has the same barrel length as the one used to test you will be pretty close most of the time. If the ammo was tested in a 24" barrel and your gun has a 22" barrel you might see 50 fps difference.

I do see differences with individual rifles, and some brands of ammo. I've seen as much as 130 fps difference between different rifles with the same length barrels with ammo from the same box. With most brands of ammo the velocity proves to be almost exactly as advertised in my guns, with some others I've seen it run 100+ fps slower than advertised.

JimPage
November 10, 2012, 09:25 AM
I've been shooting a number of years (over 55 years) and spent a lot of time worrying about velocity on various rifles. About 25 years ago I decided that it didn't really matter what the velocity was for a given load because they are usually pretty close. One or two hundred fps doesn't really matter to me.
I concentrate instead on group size and midrange trajectory. That's all the deer, moose, elk seem to worry about when I'm shooting at them. ;)

old roper
November 10, 2012, 09:59 AM
I do agree never know unless you run those loads over a chronograph.

When the 300WSM first came out member in our gun club purchase two of them plus case of win 180gr ammo. He just doesn't have the time to reload and he has the money.

We all offer to run his ammo/rifle over our chronographs with he did and he was little faster than published velocity at that time. When Tikka came out with the T-3 in 270WSM he got one of those plus case of ammo win 150gr he was in the high 3100fps with it.

My Kreiger barrel 300WSM was a 2005 270WSM in it's other life never tried factory in that rifle.

I would think your pretty close to factory velocity but my experience is based on those older WSM not the new ones. I had one 270WSM build pretty nice rifle.

sc928porsche
November 10, 2012, 10:41 AM
I have yet to fire a factory round that came within 75fps of their claim and most of them were more than 100fps slower.

jmr40
November 10, 2012, 04:47 PM
I have yet to fire a factory round that came within 75fps of their claim and most of them were more than 100fps slower.


Some rifles shoot fast, some slow because of differences in chambers and barrels. If you handload you can taylor your loads to the rifle and get the velocity quoted in loading manuals, even from slow barrels, but not necessarily with the suggested powder charge. Factory ammo has to be safe in all guns. They load to get the advertised velocity from faster guns. If they load to get that velocity from slow guns, those loads would be over pressure in fast barrels.

Some of my guns will get right at published speeds, some slightly faster, some slower. It is because of differences in individual guns, not the ammo makers.

Major Dave (retired)
November 10, 2012, 07:34 PM
likes 130 gr Win Ballistic silvertips. Best group, so far, is 0.875 inch @ 100 yards.

Others tested are:

Rem CoreLoct 130 gr, 1.3 inch
Win Power Max Bonded, 130 gr, 1.9 inch
Federal Power Shock 130 gr, 1.67 inch
Win Super X 150 gr, 1.45 inch
Federal Premium, 110 gr Barnes TTSX, 2.1 inch

The rifle is a Win Mod 70 Classic Featherweight, New Haven, with an aftermarket Canjar trigger adjusted to 2.5 lbs.

Your mileage may vary.

Unfortunately, I haven't chronographed any of these factory loads.

Bart B.
November 11, 2012, 12:08 PM
None of my bullets have had any desire to win the race to the target from the same cartridge. Just finishing that race in good shape is what's important for the most part. They've all told me that during their personal interactive moments with me as I place them snugly in case mouths. But in the loading tray nestled in cartridges they shout to the universe that they eventually must land very close together way, way down range. Why? 'Cause they're buddies; having been sealed in a box for months with other bullets without seeing the light of day, they've come to be comforted by each other. They want to stay that way at the end of their lives.