Estimation of Priming Mixture Force

Round 1

Reviewer 1 Report

The priming mixture force for primers used in 12.7 mm ammunition was estimated based on the results of pressure measurements in a closed chamber. the chamber was filled with glass balls. The authors got the force value are of the same order of magnitude as the force value of black powder. The research is worth publishing before some questions are solved. 

(1) The mathematical model need more description. 

(2) How about the detailed process of the experiment in Figure 15, 16 and 17. 

(3) The references are not enough. 

(4) It needs more explanation of the estimated and experimental results. 

Author Response

Our response is in attached file

Author Response File: Author Response.docx

Reviewer 2 Report

The quality of the position-time data could be improved in at least 2 ways. One improvement would be to increase the frame rate, perhaps approaching twice the current rate. y Measure position with a profile measurement technique.

Using polynomials to adjust motion or velocity is acceptable, but the behavior about the onset of motion is sometimes not well described. Fit the data to an appropriate mathematical expression and evaluate subsequent smoother results.

 Better fit the motion with a complex function that better duplicates the known behavior of the position and time data that was fitted to a smooth line followed by posterior derivatives.

In Figure 6 explain the dispersion more extensively.

Regarding the "Analysis of the results of modelling it is clear that the bullets can have considerable off-axis motion. the implications of this motion for accuracy should be discussed.

 If possible, it is recommended to put more current references and increase the number of references.

The conclusions should put more emphasis on transient phenomena (gas dynamics), which seem to have more influence than the reaction kinetics of the charge.

Author Response

Our response is attached file

Author Response File: Author Response.docx

Reviewer 3 Report

(1) Black powder (BP) is a diffrent pyrotechnic composite from the  modern priming composite of gun primer in energy, solid product ratio and burning rate, so its propellant force is also different. Authors used BP chatacteristics to equal to priming composite, so that the assumption will bring some  difference with real case. How much is the diffrence?

(2) In the mathematical model, authors assumpted "2.The combustion products are treated as a perfect gas; 4. The heat losses to the chamber walls are neglected". Because the combustion flow of priming composite is two reactionary flow, and the phase transitions from gas to condense phase are strong to affect the released heat of combustion and real force. Authors used a closed chamber to test pressure-time history and estimated the force, and also compared difference between calculation result and experiemntal resuts, but the comparison is too simple to analyze the availability of mathermatical model.

(3) The heat lost is from the chamber walls and filled sleeve and glass ball. If the load density is changed by filled sleeve and glass, the surfaces of sleeve and ball have to be considered to estimate force, so the heat lost will be considered in paper.

(4) The assumption lost support of theoretic evidences and experimental evidences. Authors should give the Equ.(23) is acceptable and valid.

(5) Authors will introduce detail derivation process of Equ.(24) to let reader know  its feasibility.

(6) The scatter of pressure relates to many factors, including big the match between space testing chamber with small mass,  the mass compatibility of primer, and complex two phase reaction of priming composite depended on temperature strongly. I suggest authors avoids using uncertain evidences to explain scatter resons. The evidences are important to support authors' idea and conclusions in paper. (226-279 line).

(7) Authors will pay attention to the cited format of references in paper. The cited literatures are not enough and old in Introduction. 

Comments for author File: Comments.pdf

Author Response

Our response is in attached file

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The article has been well revised, so I recommend to publish it.