Pressure Trace: PN45 N110/10x 200xtp

[TGinPA]

Pressure Trace: PN45 N110/10x 200xtp
On 3/1, I posted several traces using Re10x as the primary with sabotted 200xtp bullets. At mountainam’s request, I have tested a followup load close to one which he states is very accurate. I think it worth posting because not much load data using 10x has been posted and this followup might indicate that even further tweaking of this duplex may be possible. Of interest is the surprisingly small variance between peak pressures of the primary spike and the relatively smaller secondary spikes compared to the tracings I posted on 3/1. Two sabots were recovered intact. The relatively low peak pressures suggest that there might be some room to move to heavier powder loads or bullets with this duplex combination. Further, some temperature sensitivity is also possible – maybe not. If this load were shown to be temp sensitive, it might be interesting to see whether several more grains of booster would decrease it without diminishing accuracy. In summary, this is a potentially useful duplex load.
Gage and Module Manufacturer = RSI USB model
Trigger Sensitivity = 1, Strain Gage Voltage =4.9 Gage Factor =2.1 PSI Correction Factor: 0
Barrel Temp = 60-68 degrees F. measured at the sensor (IR). Rifle Stand: Caldwell Lead Sled
Altitude: 450 ft Chronograph: Chrony Alpha Model 8 ft from muzzle. (13 fps added to all recorded velocities to correct for distance of chrony from muzzle.)
Barrel Type: PacNor .45 Cal Muzzleloader Barrel OD = 1.06 in Barrel ID = .452
Breech Plug:Savage Std. (screw-in ventliner) ventliner orifice .032in. Sensor dist fm BP=1.1 in. Bullet Diam.= .40cal (10mm) Bullet Type = Hornady 200gr xtp Bullet weight = 200gr. ,unknurled. Sabot: Harvester Smooth Blue Sabot wgt.= 9gr. Powder:3 Traces: N110/Re10x 8/45 gr. Primer :Fed 209A
Shot fm dirty barrel. This load seemed safe in my barrel under the test conditions but may not be so in other conditions.

[Savage Shooter]

Making 560psi/gr and about 47fps/gr.

I would take this load to about 32.5kpsi and see what 2nd spike does.

I would predict 57 gr total being the right place.

For ratios I would try it 9/48 and 10/47 and expect speed at 2675fps.

[shooter]

I would like to see that same trace with 4759 10/gr and 50 gr 10x to see what that pressure would be and see if that 2nd spike went away as well.. so what do you think Mark?

[Savage Shooter]

May 9, 2011 16:54:12 GMT -5 shooter said:

I would like to see that same trace with 4759 10/gr and 50 gr 10x to see what that pressure would be and see if that 2nd spike went away as well.. so what do you think Mark?

Using 4759 instead of N110 would reduce this load pressure as traced about 1K. That would allow 2 more grains total weight above the estimates I made earlier at 57 gr so yes I would say with 4759 as booster total would be 59 or 60gr. This would gain about 80fps over using the N110 as booster at basically same pressures.

Using 4759/10x at 10/50 I would predict pressures at 32.3K with speed about 2,775fps. This is a load that would need traced as this may be real consistent on pressure ES's.

[mountainam]

This powder shows up in the Tips and Hints section and was highly recommended by RB (rest his soul) that we give it a try due to it's accuracy and consistency. I looked up the MSDS sheets on it and it says it's a double base containting 8% Nitroglycerin. My single load with this powder was 59grs. It shot very accurately-- even into the teens temp wise. But I did experience a hiccup or two after the 8th shot under single digit temps. Keep in mind that I'm using a small rifle primer in a .32ACP for ignition. So I took SW's advice and ventured into the Duplexing. My single powder 10x load clocked 2430fps. So I cautiously started with 8/48 of N110/ 10x and it was over 2500fps so I backed it off until I got to my original 2430fps. After seeing that this was accomplished with 53grs total load weight I don't think I'll go back to single powder loads. They were identically accurate groups but the ES on the duplex was way lower at 8fps for an 8shot string at 19*F. I think I'm hooked on this 10x stuff and glad I took RB's advice in the Tips section. Also, many thanks to TGinPA for all of his extra efforts. He sure answered a lot of questions with the traces.

[TGinPA]

With the thought of learning more about Re10x, I traced a series of loads containing 10x. I first tried a single powder load containing 75gr 10x in front of a sabotted 10mm 200gr xtp which gave me a funny looking trace with a peak pressure of 28kpsi and a velocity reading of 3539fps! I believe that I was looking at sabot disruption. This result lessened my enthusiasm for tracing this powder as a single with sabotted 200gr bullets in a 45 cal barrel. I then traced the following duplex loads:
Setup:as above
Bullet Diam. All traces: .40 cal. Bullet Type = Hornady 10mm 200gr xtp ,unknurled. Sabot: Harvester Smooth Blue
Powder:
1st Panel: 4759/10x 10/50gr
2nd Panel: 5744/10x 12/45gr
3rd Panel: 5744/10x 12/48gr, 12/50gr, 12/52gr
Primer :Fed 209A
Shot fm dirty barrel. This load seemed safe in my barrel under the test conditions but may not be so in other conditions.
TG

[Savage Shooter]

Amazing difference of characteristics of booster.

[TGinPA]

Pressure Trace: 5744/Re10x 10/55gr 300rem sabotless
Traces I have done to date suggest IMO that Re10x might be better suited to bullets heavier than 200gr in 45cal barrels. So, today, I traced the load shown above. Like many of deadeye’s loads, this packs a wallop on both ends. (using the BC=.213 supplied by Remington, 34 ft lbs recoil in an 11 lb rifle but less recoil than most of his with over 2000 ft lbs kinetic energy remaining at 200 yds and down less than 2 in below sight line at 200 yds if sighted 2 in. high at 100yds). From a trajectory perspective, it is possibly the equivalent of a single using about 70gr. of Re10x with the same 300gr bullet. But I don't have numbers to show it.
TG
Setup:as above
Bullet Diam. All traces: .458 cal. Bullet Type = Rem 300gr jhp resized to .448 ,unknurled. Sabot: None. Wads: lubed wool over .462x.06in. lubed fiber
Powder: All Traces:5744/10x 10/55gr
Primer :Fed 209A
Shot fm dirty barrel. This load seemed safe in my barrel under the test conditions but may not be so in other conditions.

[edge]

Not too shabby there

Combine that with the Parker bullet and it has some serious downrange potential.

edge.

[TGinPA]

Pressure Trace: 10x 75gr 300rem
In answer to what a pressure Trace of 10x as a single with a 300gr bullet looks like:
Setup: As Above. Bullet Type = 300gr .458 Rem jhp resized to .448in.,unknurled.
Sabot: None Wads: lubed wool over .462x.06 lubed fiber
Powder: All Traces: Re10x 75gr. Primer :Fed 209A
Shot fm dirty barrel. This load seemed safe in my barrel under the test conditions but may not be so in other conditions.

[mountainam]

I have a question concerning the booster amounts. I'm in the learning stages of the duplex concept and was using a booster to get the 10x started in single digit temperatures. Why do you fellows seem to like the 10 and 12gr boosters vs. a 6,7 or 8gr booster? I may be looking at this incorrectly but, I'd rather let the 10x flatten out the curve rather than the booster provide a sharp spike. I'd rather get 1000 boosters per pound using 7 grs than 700 boosters by using 10grs. In trying to analyze these traces doesn't it seem that VV N-110 holds these loads to a smaller variance in peak pressures than do either of the AA5744 or SR4759 boosters?
TGin PA, You are a REAL MAN to be able to take those 300gr tests. By the looks of the secondary spikes they must produce some pretty high muzzle lift? Anyhow, straighten me out on my observations. Thanks!

[TGinPA]

Mountainam: My assumed tolerance for recoil discomfort is aided a just a bit by a lead sled containing 50 lbs of lead shot between me and the gun. ;D
In regard to your questions about type and amount of booster, they are all good ones with many different answers. Considering all the variables, your answer to these questions may justifiably and logically be different than mine or anyone else's. Among the more obvious variables are expense, component availability, ignition, pressure/velocity change with temperature, light bullets, bullet performance at different velocities and ranges, sabot integrity, range, and accuracy considerations. IMO, it depends on what one wants to achieve and how many compromises one is willing to make. For instance, I have in mind a deer load which I faithfully use for my 50cal. every fall. Considering the variables above, it would take me either 4 words ("it works for me") or at least a page to try to logically justify how I came to use it. In my years on this board, I have seen only one posted load even close to it.
TG

[Dave W]

May 13, 2011 16:47:20 GMT -5 TGinPA said:

Mountainam: My assumed tolerance for recoil discomfort is aided a just a bit by a lead sled containing 50 lbs of lead shot between me and the gun. ;D
In regard to your questions about type and amount of booster, they are all good ones with many different answers. Considering all the variables, your answer to these questions may justifiably and logically be different than mine or anyone else's. Among the more obvious variables are expense, component availability, ignition, pressure/velocity change with temperature, light bullets, bullet performance at different velocities and ranges, sabot integrity, range, and accuracy considerations. IMO, it depends on what one wants to achieve and how many compromises one is willing to make. For instance, I have in mind a deer load which I faithfully use for my 50cal. every fall. Considering the variables above, it would take me either 4 words ("it works for me") or at least a page to try to logically justify how I came to use it. In my years on this board, I have seen only one posted load even close to it.
TG

Mind sharing what this load is?

As far as booster amounts. I usually look at the reloading manuals and get Edge to give me a QL estimate on what the primary should do as a single at a certain charge weight for speed. Then reduce the primary and start adding booster to get the velocity window I'm looking for. Depending on the components, muzzle flash, etc., the sweet spot usually works out to be in the 10-12gr range with H322 & 2015. I have never been able to use more than 10gr of N110 as booster paired with H322 with saboted bullets in the .45 without sabot failure so it was a necessity to keep the booster at that limit.