chronograph a .270 130 grain Remington?

[jersey joe]

Has anyone ever chronographed a factory Remington .270 130 grain PSP Core-Lockt? I realize I could buy a chrono but for what I wish to spend I imagine the results would be all over the place. I am pretty sure that this group has better experience than moi.

Here's the deal. My Savage 270 does very well, accuracy wise, with good ol' Rem Core-Lokt PSP 130's but I find the ballistics not as accurate. The muzzle velocity suggests a MV of 3060 with a 24" barrel but my, every man results with a 22" barrel, do not match the stats. With a 200 yard zero I am plus two inches at 100 yards (greater than the suggested 1.5 inches). If I zero at 100 yards I am minus four plus inches at 200 yards compared to the published three. I fully understand that my ability is a factor but I wonder if the velocity is less than published. I have found that two inches off the barrel might yield 75 less FPS but not enough to match my experience. I have needed to back to off to an approximate 2900 FPS for my 130 grain PSPs to match my experience. I am not looking to find fault with published stats but only looking to validate a suspicion.
Any thoughts?

 

[Don Fischer]

Ya know, we went years without knowing what velocity our ammo was doing. Sometimes I think we were better off then! Old school thought was zero it 3" high at 100 yds and your good to go. I would shoot it at ranges you expect to shoot though just to know where you are.

 

[emcon5]

I personally wouldn't pay much attention to the advertised muzzle velocity.

Make sure whatever it is you are using for your calculations matches your reality. Use a ballistics program like JBM, measure and input your sight height, and make sure your environment variables are input properly, particularly your altitude.

Even if it is only 2900 FPS, that will still kill pretty much any game animal in North America.

 

[bamaranger]

.270

I've got a 22" barreled Rem 700 ADL in cal. 270. It will not make 3000 fps w/ a 130 gr bullet with any load in my manuals that say it should.....meaning, it is a "slow" rifle. I've got a pal who I shoot and load with, his Rem 700 w/ 24" barrel will easily break 3000 fps with a 130gr s with about any reasonable combo he runs through it, ....he has a "fast" rifle (and 2 more inches of barrel).

I personally think that to get the real benefits of a .270 w/o a lot of fuss, that a 24" tube is the way to go, but for quite a few years, 22 inchers were all that Rem produced. My rifle has other quirks, it tends to copper foul easily past 20 rds, but if kept squeaky clean, is sub MOA accurate. It also has the enduring trait of plunking a wide range of bullet weights, from 110-150 grains, into the same POI at 100 yds. Were it not for those aspects, I'd likely have that 22" tube off and get a 24" from somebody.

A few years back I finally got a chrono. I was shocked to learn that my very accurate 130 gr Ballistic Tip load was running sub 2900 and not the 3000 fps+ the manual said it should. Velocity aside, that "slow" load killed deer just fine at the ranges I shoot them at. Unless your're really stretching the
reach of your .270, I wouldn't get too hung up about a "slow" rifle.

 

[FrankenMauser]

I ran some across my chronograph quite some time ago. 22" barrel, 2,990 fps.
That barrel tends to run "slow", though. Other rifles probably would have pooped those bullets out a bit faster.
And, of course, that number is only valid for the lot number that I had for testing.


What suspicion are you trying to validate? It is not clear to me.

 

[Doyle]

Ranger, sounds like your Remington barrel would benefit from an afternoon with a Flitz soaked bore mop.

 

[jersey joe]

My journey started with trying to calibrate the reticle hash marks on my scope. According to the Leupold doc a MV of 3050 and 200 yard zero suggests that the next lower hash mark corresponds with 6.9" low at 300 yards. I got zeroed at 200 but found that I was much higher at 100 than the stated 1.5" by Remington. Without a chrono I backed off the MV in order to fit the trajectory profile. This was all to understand where I would be at 300 yards since I don't have a 300 yard range nearby.

 

[RC20]

I have found field results is what counts so when I setup I use field results.

Ergo, enough off variables and you are low, want on at 200? Move it up a half inch.

 

[emcon5]

I got zeroed at 200 but found that I was much higher at 100 than the stated 1.5" by Remington.

Instead of looking at a generic chart from Remington, run the numbers in an actual ballistics program with details for your rifle (sight height) and the altitude where you will be shooting.

 

[Bart B.]

A given load can easily produce a 150 fps spread in average velocity across all barrels of the same length.

A 40 fps spread in average velocity for a given load and rifle shot by several people is normal.

 

[bamaranger]

the fouler

Doyle, it's some better these days, shot and cleaned periodically for near 20 yrs, including a couple of really serious treatments with JB Bore polish. But it's still "slow". So much so, that I quit using 130 gr bullets and switched to Sierra 110's, cause I just had to break 3000 fps. The 110's will indeed break 3000, and then some, but I do not run them that hard. I've recently been interested in the 6.8mm bullets that are bonded and tipped, but have not bought any.

I really dandy walnut ADL stock came my way and looks good on the fouler. I checked zero on last month and intend to hunt it again this season.

 

[Scorch]

sounds like your Remington barrel would benefit from an afternoon with a Flitz soaked bore mop

Fairly common advice from some, and bad advice whenever it is given. A bore mop will not provide a solid backing, so the bore will be polished unevenly.

 

[jmr40]

A given load can easily produce a 150 fps spread in average velocity across all barrels of the same length.

A 40 fps spread in average velocity for a given load and rifle shot by several people is normal.

This is one of those things most people don't consider. I've seen as much as 130 fps with 2 different 30-06 rifles shooting the same ammo from the same length barrel. I have two 30-06 rifles, both with 22" barrels; one is consistently 80-100 fps faster than the other depending on the load.

I have 4 rifles in 308, the one with the 20" barrel is consistently the fastest, beating one of the 22" barreled guns by 40-50 fps and the other by 20-25 fps. The rifle with an 18" barrel is only about 50-60 fps slower than the 22" rifles.

In my experience shooting factory loads they are usually at least 100 fps slower than advertised in my rifles. Sometimes more. I have always been able to match the numbers shown in my load manuals with my hand loads.

You are very likely shooting slower than advertised. The 2" of barrel probably accounts for 40-50 fps of it. Your rifle may well just be slower than normal, and the factory loads are probably slower than advertised. All of which is pretty normal. But as long as you know what the drops are at the ranges you plan to shoot at it isn't a huge problem. Should still have enough power down range to get the job done.

If this is important going to a bullet with a higher BC will mean much more speed down range and less drop even though it may start slower than expected.

 

[jersey joe]

I never heard of slower barrels but that’s why I appreciate this site. I am always learning something new. I guess variability is my lot in life if I choose commercial ammo. I can’t complain though because the rifle does really well with it. Thanks guys for the education.

 

[2ndtimer]

I chrongraphed some Remington 270 Win. 130 gr CoreLockts out of my 22" barrel Marlin XL7 a year or two ago. The Remington ammo failed to top 2850 fps. I also chronographed some Federal Power Shok (Blue box) 130 gr at the same time and it topped 2960 fps, and was more accurate in that particular rifle. Handloads in that rifle can top 3,000 fps with Nosler 130 gr Ballistic Tips and Alliant Power Pro 4000-MR. Not sure a deer could tell the difference, but if I can pick up an extra 100 fps with better accuracy, I tend to go that way.

 

[jersey joe]

Wow, thanks for the update. My actual results look very much like that velocity.
I agree this won't matter to the critter but as I mentioned I am merely trying to calibrate the hash marks on my scope. Thanks again.

 

[emcon5]

I am merely trying to calibrate the hash marks on my scope. Thanks again.

Here are a couple of suggestions that can actually solve your problem.

Make sure whatever it is you are using for your calculations matches your reality. Use a ballistics program like JBM, measure and input your sight height, and make sure your environment variables are input properly, particularly your altitude.

Instead of looking at a generic chart from Remington, run the numbers in an actual ballistics program with details for your rifle (sight height) and the altitude where you will be shooting.

Just a thought......

 

[Bart B.]

All the commercial rifle barrel groove diameters I've measured are bigger than, and often lengths are shorter than, SAAMI spec test barrels. In contrast, most match grade barrel's groove diameters are usually smaller than specs for best accuracy.

If ammo makers use SAAMI spec test barrels establishing velocity data, most commercial barrels will shoot their bullets slower. Match grade barrels will shoot 'em faster

 

[jersey joe]

I appreciate your input emcon5. I have been using three different calculators including JBM and a major input to any calculator is the muzzle velocity. I do not have a chrono and my actual results did not match the trajectory of the published velocity. I backed into a muzzle velocity by trial and error manipulating MV to match my results. My estimate of MV came up fairly short of published numbers and was the reason for the investigation.

 

[T. O'Heir]

The advertised muzzle velocity isn't an exact number. It'll vary according to a swarm of variables.
"...out of my 22" barrel..." Remington probably used a universal receiver with a 24" barrel.
"...calibrate the hash marks on my scope..." MV has nothing to do with that. That's done on a range. You want to know where a shot hits at specific distances when aiming with each mark. As in how much hold over is each mark.
Forget any ballistics program. There are far too many variables involved.