max 2775 fps .why not more?

[sport20]

hi guys
specs are
sendero 7mm mag
.005 of lands, seems to be best accuracy
162 grn berger vlds
rem and fed brass
both fed and wlmr mag primers

I've tried H1000 and at maxium load of 70 grns im getting 2775 fps.
also tried h 4831sc and at max load of 66 grs im getting 2700 fps
what type of powder do HSM use to be able to achieve over 3000 fps.
any advise is appreciated
thanks

 

[MTBULLET]

Reconfirm velocity with different chrono

 

[sport20]

hi mtbullet
this was confirmed by shooting at different ranges using a strelok ballistic calculator.
thanks

 

[Barrelnut]

hi mtbullet
this was confirmed by shooting at different ranges using a strelok ballistic calculator.
thanks

This is probably not accurate enough. Sometimes you need confirmation with another tool. The suggestion to use a chrony is a good one.

Is the bullet a Berger or a Hornady? I did not know Berger made a 162 gr 7mm bullet?

 

[sport20]

Sorry 168 gr berger. I've beenshooting at 400 ,700,900 yards and when I feed all info into ballistic calculator it gives me my click valu adjustments. I've been hitting these targets so my fps must be right. According to gun weeks this is the best way to confirm.
Thanks

 

[Barrelnut]

Well they do say to confirm and that is a good idea, but with 70 Gr of h1000 with a 168 Gr bullet in a 7MM RM, it is probably running a lot closer to 3000 FPS from a 26" barrel. That is a well documented load, so something is off in the calculations somewhere. Are you running an 18" barrel, but it was stated as a Sendero which have 26" barrel, I believe.

 

[sport20]

26 inch barrel but I can't figure out if I'm doing something wrong because I am filling in all the correct values When I use 27 75 ft./s I hit the target at different ranges

 

[bigedp51]

With Quickload at its default settings with a 26 inch barrel it predicts 2971 fps with your H1000 load. If I knew your case capacity and OAL it would be a closer reading.

 

[sport20]

3.442". When I go over 70 grains I get pressure marks and even sometimes the casing jams in the gun

 

[bigedp51]

3.442". When I go over 70 grains I get pressure marks and even sometimes the casing jams in the gun

Default Quickload settings, .284, 168, Berger VLD #28401 OAL 3.290, case capacity 82 grains of H2O, 70 grains of H1000, velocity 3016 at 60,064 psi chamber pressure.

Reset Quickload to OAL 3.442, velocity drops to 2958 at 55,555 psi.

The above is why you need a chronograph with Quickload. You then adjust the burn rate of the powder until Quickload velocity matches the chronograph.

I went to a webpage that lists case capacities and it lists 84 grains of H2O for the 7mm mag and this drops the velocity to 2916 and a chamber pressure of 52,371 psi.

What I can tell you is Federal and Remington have the softest brass in the order. Meaning they will start to flow into the ejector before Winchester and other harder brands of brass.

Bottom line, Quickload and phone apps are computer generated guesstimates, and with information you have given I think both software programs are giving bad guesses. And the marks on the base of your case are far more accurate.

I bought a MagnetoSpeed Sporter to test my loads which are not computer generated guesses. (subliminal suggestion)

I'm 65 and have been reloading for over 47 years and in the last 10 years I have bought tools and gadgets to "help" in reloading. The problem is many of gadgets do not make my groups smaller. New glasses help the most and I'm hoping someone invents cheap laser guided bullets.

 

[sport20]

lol. thanks for info bigedp51 but i never had much luck with winchester brass,getting pressure marks at 69 grains but i will try and get a chronograph and go from there. it is possible i am missing something and i appreciate the info from a veteran like yourself

 

[PowellSixO]

Are you putting the proper information in? Scope height, elevation, temp, barrel twist, humidity, and other information does have an effect. The more accurate you are on the information you put in, the more accurate the information you get back.

 

[sport20]

Yes sir. All info entered correctly

 

[sport20]

What is your velocity with 69 grs h1000